M
- MACE
See: Macintosh Audio Compression and Expansion (MACE)
- machine information record
- A data structure that contains information about the state of the machine at the time an exception occurs. Defined by the MachineInformation data type.
- Machine State Register
- A 32-bit PowerPC supervisor-level register that records the state of the processor, including if floating-point instructions and floating-point exceptions are enabled.
- Macintosh Audio Compression and Expansion (MACE)
- A set of Sound Manager routines that allow your application to compress and expand audio data.
- Macintosh character set
- The characters and character codes originally defined for the Macintosh computer. The Macintosh character set consists of the ASCII character set, plus additional characters (sometimes called high ASCII or extended ASCII) with character codes between $80 and $D8
See also: Standard Roman character set
- Macintosh Easy Open
- The part of the Macintosh system software that provides translation services for users of Macintosh computers. Macintosh Easy Open uses the Translation Manager to provide these services.
- Macintosh file system (MFS)
- A now-obsolete method of organizing files on a volume in a 'flat' or nonhierarchical structure
- Macintosh interface functions
- A set of Macintosh-specific functions. Most other QuickDraw GX functions can exist on any platform.
- Macintosh Programmer's Workshop (MPW)
- A software development system for the Macintosh family of computers provided by Apple Computer.
- Macintosh script management system
- The Script Manager, script-aware parts of other text managers, the WorldScript extensions, and one or more script systems.
- Macintosh system software
- A collection of routines that you can use to simplify your development of Macintosh applications.
- Macintosh Toolbox
See: Human Interface Toolbox
- Macintosh User Interface Toolbox
See: Macintosh Toolbox
- macro
- A sequence of predefined directives that the C preprocessor interprets at compile time. When the preprocessor encounters the macro name in the source code, the preprocessor substitutes the macro definition for it. QuickDraw GX provides macros for number format conversions.
- MacsBug
- A Macintosh debugging utility.
- MacTCP
- A Macintosh utility program that provides the TCP/IP support needed to connect to the Internet. A separate communications program is needed to connect via Serial Line Internet Protocol (SLIP) or Point-to-Point Protocol (PPP).
- mail
- A term used to refer collectively to letters.
- mailer
- A region added to a document window that transforms the document into a letter. The mailer enables the user to enter addresses and subject information, enclose other files and folders in the letter, and add a digital signature to the letter.
- mailer set
- All of the mailers belonging to a forwarded letter.
- mail slot
- A personal MSAM slot that serves to transfer letters
See also: slot
- main aspect
- An aspect that contains the properties the CE needs to fill in the data for an item in a sublist
See also: main view aspect
- main aspect template
- A template for a main aspect.
- main dictionary
- A dictionary that contains most of the information used by an input method for its conversion operations
See also: user dictionary
- main enclosure
See: content enclosure
- main routine
- A function contained in a fragment whose use depends on the kind of fragment it is in. For applications, the main routine is the usual entry point
See also: main symbol
- main screen
- In a drawing environment with multiple screens, the screen with the menu bar. QuickDraw maps the (0,0) origin point of the coordinate plane to the main screen's upper-left corner, and other screens are positioned adjacent to it
See also: startup screen
- main segment
- In 68K-based runtime architectures, the segment that contains the main entry point.
- main symbol
- For applications, the main routine or main entry point. Shared libraries do not require a main symbol.
- main view aspect
- An aspect that provides the properties for all the views in the main portion of an information page; that is, all of the information page except for the items in a sublist
See also: main aspect
- major error
- The amount of line layout error that a printer driver applies to the space glyph.
- major glyph
- On a printed page, a space glyph, to which printer drivers apply most of the line layout error
See also: minor glyph
- major switch
- A change of the foreground process. The Process Manager switches the context of the foreground process with the context of a background process (including the A5 worlds and low-memory globals) and brings the background process to the front, sending the previous foreground process to the background
See also: context, minor switch
- Make Changes privileges
- The directory access privileges that allow other users to create, rename, delete, and write files in the specified directory.
- manager
- A library or set of related libraries that defines a programming interface to the Mac OS. For example, the Memory Manager is a library of routines that helps developers allocate and release memory for their programs.
- mantissa
See: significand
- map
See: mapping
- mapping
- (1) A 3 by 3 matrix"a property of a format object that specifies scaling and orientation. (2) A 3 by 3 matrix"a property of a transform object, view port object, and view device object"that specifies the translation, rotation, or distortion to be applied to a shape when it is drawn. (3) A transformation of spatial locations (points) that can be represented by a 3 by 3 perspective matrix. Synonymous with map and mapping matrix.
- mapping matrix
See: mapping
- map node
- A node that contains an additional map record.
- map record
- A record in a header node or map node that indicates which nodes in a B*-tree file are used and which are not.
- margins
- The left, right, top, and bottom sides of the text area.
- mark
See: file mark
- marking callback functions
- Object callback functions that allow your application to use its own marking scheme rather than tokens when identifying large groups of Apple event objects
See also: mark-adjusting function, mark token function, object callback function, object-marking function
- mark count
- The number of times the Apple Event Manager has called the marking function for the current mark token. Applications that support marking callback functions should associate the mark count with each Apple event object they mark.
- mark token
- A token returned by a mark token function. A mark token identifies the way an application marks Apple event objects during the current sessions while resolving a single test. A mark token does not identify a specific Apple event object; rather, it allows an application that supports marking callback functions to associate a group of objects with a marked set.
- mark token function
- A marking callback function that returns a mark token.
- mark-adjusting function
- A marking callback function that unmarks objects previously marked by a call to an application's marking function.
- mask region
- A 1-bit-deep region that defines how an image is to be displayed in the destination coordinate system. For example, during decompression the Image Compression Manager displays only those pixels in the source image that correspond to bits in the mask region that are set to 1. Mask regions must be defined in the destination coordinate system.
- master clock component
- A movie's clock component.
- master directory block (MDB)
- The part of a volume that contains information about the volume, such as the volume name and allocation block size.
- Master Key password
- The password of the principal user of a computer. This password unlocks the local identity and provides access to the services represented in the PowerTalk Setup catalog.
- master pointer
- A pointer to a relocatable block, maintained by the Memory Manager and updated whenever the block is moved, purged, or reallocated. All handles to a relocatable block refer to it by double indirection through the master pointer.
- master pointer block
- A nonrelocatable block of memory that contains master pointers. A master pointer block in your application heap contains 64 master pointers, and a master pointer block in the system heap contains 32 master pointers.
- master pointer flag bits
- The high-order 8 bits of a master pointer. In 24-bit addressing mode, some of these bits are used to store information about the relocatable block referenced by the master pointer.
- MathLib
See: PowerPC Numerics library
- math baseline
- The baseline used for setting mathematical expressions; it is centered on operators such as the minus sign.
- matrix
See: transformation matrix
- matte
See: blend matte, track matte
- maximum mode
- A transfer mode type in which the source component replaces the destination component only if the source component has a larger value.
- maximum source rectangle
- A rectangle representing the maximum source area that a video digitizer component can grab. This rectangle usually encompasses both the vertical and horizontal blanking areas.
- MB
- Abbreviation for megabyte. A megabyte is 1024 kilobytes, or 1,048,576 bytes.
- MC680x0 bit-numbering
- The bit-numbering scheme used by Motorola. Bit numbers are counted from right to left. (That is, the most significant bit has the highest bit number, and the least significant bit number has the lowest bit number.) Compare reversed bit-numbering.
- MDB
See: master directory block (MDB)
- media
- A Movie Toolbox data structure that contains information that describes the data for a track in a movie. Note that a media does not contain its data; rather, a media contains a reference to its data, which may be stored on disk, CD-ROM disc, or any other mass storage device.
- media handler
- A piece of software that is responsible for mapping from the movie's time coordinate system to the media's time coordinate system. The media handler also interprets the media's data. The data handler for the media is responsible for reading and writing the media's data
See also: base media handler component, derived media handler component
- media information
- Control information about a media's data that is stored in the media structure by the appropriate media handler.
- megahertz (MHz)
- A unit of frequency, equal to one million cycles per second.
- memory address
See: logical address, physical address
- memory allocation
- A range of logical addresses used for storing a particular piece of data, such as a global variable or a data structure. A memory allocation can range in size from 1 byte to multiple pages.
- memory block
- An area of contiguous memory within a heap.
- memory cushion
- An application-defined threshold below which the application should refuse to honor any requests to allocate memory for nonessential operations.
- memory location record
- A data structure that provides information about the location of a fragment in memory. Defined by the MemFragment data type.
- memory management unit (MMU)
- Any component that performs address mapping in a Macintosh computer. In Macintosh II computers, it is either the Address Management Unit (AMU) or the Paged Memory Management Unit (PMMU). The MMU function is built into the MC68030 and MC68040 microprocessors.
- Memory Manager
- The part of the Operating System that dynamically allocates and releases memory space in the heap.
- memory map
- memory reservation
- The process of creating a free space at the bottom of the heap for a newly allocated block by moving unlocked relocatable blocks upward.
- memory reserve
- An allocated block of memory in the application heap that is held in reserve and released only for essential operations when memory in the heap is low.
- memory size
- The number of bytes of random access memory allocated to the QuickDraw GX graphics client. The default size is 600 KB.
- memory-block record
- A data structure used by the translation parameter block to indicate the starting address and length of a given block of memory. This parameter block is defined by the MemoryBlock data type.
- memory-mapped file
- A disk file whose contents are mapped into a memory area. A virtual memory system transfers portions of these contents from the file's permanent location on disk to physical memory as needed in response to page faults. Thus, the disk file (instead of a separate scratch file) serves as backing store for the code or data not immediately needed in physical memory.
- menu
- A user interface element you can use in your application to allow the user to view or choose an item from a list of choices and commands that your application provides
See also: contextual menu, hierarchical menu, pop-up menu, pull-down menu, submenu
- menu bar
- A rectangle that extends across the top of the main screen and contains titles or icons that the user can select to use pull-down menus.
- menu bar definition function
- A function that draws the menu bar and performs most of the drawing activities related to the display of menus when the user moves the cursor between menus. This function, in conjunction with the menu definition procedure, defines the general appearance and behavior of menus.
- menu bar entry
- A menu color entry record that contains 0 in both the mctID and mctItem fields. A menu bar entry defines the color for an application's menu bar and defines default colors for its menu titles, menu items, and background color of menus.
- menu bar resource
- A resource (of type 'MBAR') that specifies the order and resource ID of each menu in a menu bar.
- menu color entry record
- A data structure of type MCEntry that defines the colors for an application's menu bar, menus, or menu items. The first two fields of a menu color entry record, mctID and mctItem, define whether the entry is a menu bar entry, a menu title entry, or a menu item entry.
- menu color information table
- An array of menu color entry records, maintained by the Menu Manager, that define the standard color for the menu bar, titles of menus, text and characteristics of menu items, and background color of a displayed menu. If you do not add any entries to this table, the Menu Manager draws your menus using the default colors, black on white.
- menu color information table resource
- A resource (of type 'mctb') that specifies the colors for an application's menu bar, menus, and menu items.
- menu definition procedure
- A procedure that performs all the drawing of menu items within a specific menu. This procedure, in conjunction with the menu bar definition function, defines the general appearance and behavior of menus.
- menu ID
- A number that you assign to a menu in your application. Each menu in your application must have a unique menu ID.
- menu item
- In a menu, a command or setting that the user can choose.
- menu item entry
- A menu color entry record that contains nonzero values in both the mctID and mctItem fields. A menu item entry defines colors for the mark, text, and keyboard equivalent of items in a specific menu. It also defines the default background color of a menu.
- menu list
- A per-application data structure, maintained by the Menu Manager, containing a list of all current pull-down and pop-up menus, including both enabled and disabled menus.
- Menu Manager
- The part of the Mac OS that manages the creation, display, and behavior of menus
See also: menu
- menu record
- A data structure of type MenuInfo that the Menu Manager uses to maintain information about a menu.
- menu resource
- A resource (of type 'MENU') that specifies the menu title and the individual characteristics of items in a menu.
- menu title
- The word or icon in the menu bar or in a window that shows the location of a menu.
- menu title entry
- A menu color entry record that contains a nonzero value in the mctID field and contains 0 in the mctItem field. A menu title entry defines colors for the title, items, and background color of a specific menu. It also defines the default menu bar color.
- menu-blink time
- The number of times a menu item blinks when the user chooses it.
- menu-item component
- The portion of an 'hmnu' resource in which you specify the help messages for a particular menu item.
- menu-title component
- The portion of an 'hmnu' resource in which you specify help messages for the menu title.
- message
- (1) The basic unit of communication defined by the Interprogram Messaging Manager. The term message is used as an inclusive term to refer both to letters and non-letter messages
See also: letter
- message block
- (1) A component of a message consisting of a sequence of any number of bytes whose format is governed by the block creator and block type. (2) A byte stream that an open application uses to send data to and receive data from another open application (which can be located on the same computer or across a network). The PPC Toolbox delivers message blocks to an application in the same sequence in which they were sent.
- message chain
- One or more handlers that wish to receive and respond to messages. A handler at the top of a message chain always receives a message first
See also: message handler
- message class
- The set of messages and methods defined at run time that are understood by message objects.
- message creator
- A four-character sequence that indicates which application created a message; analogous to a file's creator in HFS.
- message family
- A set of messages grouped according to similar characteristics. Messages of the same family conform to the syntax of a defined set of message block types and their associated semantics.
- message handler
- A recipient of messages. In QuickDraw GX printing, applications, printing extensions, printer drivers, and QuickDraw GX are all message handlers, which are part of a message chain.
- message header
- That part of a message that contains control information about the message such as the message creator and message type, the total length of the message, the time it was submitted, addressing information, and so forth.
- Message Manager
- A part of system software, related to QuickDraw GX, that manages messages.
- message mark
- A marker, used by the IPM Manager, that points to the current location within a message that is being created.
- message object
- The recipient and sender of messages.
- message override
- The response, by a message handler, of intercepting a message and taking some action. The response to a message is performed by an override function
See also: override function
- message phase
- The phase in which SCSI devices exchange message information.
- message queue
- A set of messages maintained by the IPM Manager on a recipient's disk or the disk of a message server.
- message summary
- A set of data used by the Finder to display an incoming letter to a user.
- message type
- A code that indicates the semantics of the message, the block types the message should contain, and the relationships among the various blocks in the message.
- message-passing architecture
- A software system driven by messages that are sent in response to certain conditions or events. The messages activate message handlers, which take action in response to the messages. QuickDraw GX printing uses a message-passing architecture.
- messaging service access module (MSAM)
- A foreground or background application that makes an external messaging system accessible from within an AOCE system. It translates and transfers letters, non-letter messages, or both between an AOCE system and an external messaging system
- messaging slot
- A personal MSAM slot that serves to transfer non-letter messages
See also: slot
- messaging system
- A combination of hardware and software that gives users or processes the ability to exchange messages.
- method
- A function defined by a particular class in an object-oriented programming environment
See also: dot type
- MFS
See: Macintosh file system (MFS)
- MFS volume
- A volume that is organized using the Macintosh file system.
- MHz
See: megahertz (MHz)
- microsecond
- A unit of time equal to one millionth of a second. Abbreviated
µ
sec.
- MIDI
See: Musical Instrument Digital Interface (MIDI)
- MIDI Manager
- The part of the Macintosh system software that controls the flow of MIDI data and commands through a MIDI interface.
- MIDI note value
- An integer that is defined to correspond to a frequency specified in hertz that is associated with a musical note.
- migrate mode
- A transfer mode type in which the destination color component is moved toward the source component by the value of the step specified in the operand component.
- millisecond
- A unit of time equal to one thousandth of a second. Abbreviated ms.
- minimum evaluation format
- The narrowest format in which a floating-point operation can be performed. Each implementation of PowerPC Numerics defines its own minimum evaluation format.
- minimum mode
- A transfer mode type in which the source component replaces the destination component only if the source component has a smaller value.
- minimum partition size
- The actual partition size limit below which an application cannot run.
- mini icons
- Icons of resource types 'icm#', 'icm4', and 'icm8' that measure 12 by 16 pixels. Like the icons in an icon family, the three resource types for mini icons identify the icon list, 4-bit color icons, and 8-bit color icons, respectively
See also: small icon resource
- mini-A5 world
- An area of memory created and maintained by the Process Manager for a native PowerPC application. A native application's mini-A5 world contains a pointer to the application's QuickDraw global variables
See also: A5 world
- minor error
- The amount of line layout error that a printer driver applies to nonspace glyphs.
- minor glyph
- On a printed page, a nonspace glyph, to which printer drivers apply the line layout error that remains after applying most of the error to major glyphs.
- minor slot space
- An Apple-specific term that describes the first megabyte of the 16 MB standard slot space.
- minor switch
- A change in the context of a process. The Process Manager switches the context of a process to give time to a background process without bringing the background process to the front
See also: context, major switch
- missing character glyph
- The glyph in a font that is drawn when no glyph is defined for a character code in a font.
- missing-items component
- The portion of a help resource in which you specify help messages for any items missing from or unspecified in the rest of the resource.
- miter
- The length a sharp join can reach before being truncated.
- mixed environment
- A process execution environment that supports applications and other software written in more than one instruction set.
- Mixed Mode Manager
- The part of the Mac OS that allows code with different calling conventions to call each other. For example, the Mixed Mode Manager makes it possible for PowerPC code to call emulated classic 68K code.
- mixed state
- The condition of a control, such as a radio button or checkbox, that occurs when the selection indicated by the control contains some data in the on state and some in the off state.
- mixed-directional text
- The combination of writing systems with left-to-right and right-to-left directions"within a single line of text.
- MMU
See: memory management unit (MMU)
- modal dialog box
- A dialog box that puts the computer in a state, or 'mode,' in which the user can work only inside the dialog box
See also: dialog box, modeless dialog box, movable modal dialog box
- modal dialog filter function
- An application-defined function that filters events passed from the Event Manager to your application when one of its modal dialog boxes is being displayed.
- modeless dialog box
- A dialog box that resembles a document window without a collapse box. The user can move a modeless dialog box, make it inactive and active again, and close it like a document window
See also: dialog box, modal dialog box, movable modal dialog box
- modeless dialog frame
- A control that provides an Appearance-compliant border for the content region of non-standard modeless dialog boxes.
- modes
See: access modes, deny modes
- mode switch
- The process of switching the execution context between the CPU's native context and an emulator (for example, the 68LC040 Emulator)
See also: switch frame
- modifier keys
- Non-character keys, such as Command, Option, and Control, which can be combined with character keys to form keyboard equivalents.
- modulation of speech
See: pitch modulation
- module
- A contiguous region of memory that contains code or static data; the smallest unit of memory that is included or removed by the linker
See also: segment
- monitors extension
- An extension to the Monitors control panel that a video card manufacturer can develop and provide to give users a simple way to control features of the video card. A monitors extension is limited to the video card; it cannot be used to control the settings of systemwide features. A user can open an extension only through the Monitors control panel.
- monitors extension file
- A file of type 'cdev' that contains required and optional resources that implement an extension to the Monitors control panel for a specific video card. One of the required resources is a code resource containing a monitors extension function.
- monitors extension function
- A function that interacts and communicates with the Monitors control panel, responding to requests from the Monitors control panel to handle events and perform actions. Every implementation of an extension to the Monitors control panel must contain a monitors extension function in the monitors code ('mntr') resource.
- monophonic sound.
- Sound consisting of a single channel
See also: stereo sound
- monospaced font
See: fixed-width font
- monostyled edit record
- A TextEdit record used to contain text that is set in a single font, size, and face.
- most significant bit
- The bit contributing the greatest value in a string of bits. For example, in the MC680x0 numbering scheme bit number 7 in a byte contributes a value of 27, or 128. Same as high-order bit
See also: least significant bit
- mount
- To make a volume available on the local machine.
- mounted volume
- A volume that has had its descriptive information read by the File Manager and placed into a volume control block in memory.
- mouse location
- The location of the cursor at the time an event occurred.
- mouse scaling
- A feature that causes the cursor to move twice as far during a mouse stroke as it would have otherwise, provided the change in the cursor's position exceeds the mouse-scaling threshold within one tick after the mouse is moved.
- mouse-down event
- An event indicating that the user pressed the mouse button.
- mouse-down region
- The region between the caret position and the middle of an adjacent character that maps unambiguously to a single character offset.
- mouse-moved event
- An event indicating that the cursor is outside of a specified region.
- mouse-scaling threshold
- A number of pixels that, if exceeded by the sum of the horizontal and vertical changes in the cursor's position during one tick of mouse movement, causes mouse scaling to occur (if that feature is turned on); normally six pixels.
- mouse-up event
- An event indicating that the user released the mouse button.
- movable alert box
- An alert box with a title bar that allows the user to move the alert box
See also: alert box
- movable modal dialog box
- A modal dialog box that has a title bar (with no close box) by which the user can drag the dialog box
See also: dialog box, modal dialog box, modeless dialog box
- movie
- A set of time-based data that is managed by the Movie Toolbox. A QuickTime movie may contain sound, video, animation, laboratory results, financial data, or a combination of any of these types of time-based data. A QuickTime movie contains one or more tracks; each track represents a single data stream in the movie.
- movie boundary region
- A region that describes the area occupied by a movie in the movie coordinate system, before the movie has been clipped by the movie clipping region. A movie's boundary region is built up from the track movie boundary regions for each of the movie's tracks.
- movie box
- A rectangle that completely encloses the movie display boundary region. The movie box is defined in the display coordinate system.
- movie clipping region
- The clipping region of a movie in the movie's coordinate system. The Movie Toolbox applies the movie's clipping region to the movie boundary region to obtain a clipped movie boundary region. Only that portion of the movie that lies in the clipped movie boundary region is then transformed into an image in the display coordinate system.
- movie controller component
- A component that manages movie controllers, which present a user interface for playing and editing movies.
- movie data exchange component
- A component that allows applications to move various types of data into and out of a QuickTime movie. The two types of data exchange components, which provide data conversion services to and from standard QuickTime movie data formats, are the movie import component and the movie export component.
- movie data export component
- A component that converts QuickTime movie data into other formats.
- movie data import component
- A component that converts other data formats into QuickTime movie data format.
- movie display boundary region
- A region that describes the display area occupied by a movie in the display coordinate system, before the movie has been clipped by the movie display clipping region.
- movie display clipping region
- The clipping region of a movie in the display coordinate system. Only that portion of the movie that lies in the clipping region is visible to the user. The Movie Toolbox applies the movie's display clipping region to the movie display boundary region to obtain the visible image.
- movie file
- A QuickTime file that stores all information about the movie in a Macintosh resource, and stores all the associated data for the movie separately. The resource is stored in the resource fork, and the data in the data fork. Most QuickTime movies are stored in files with double forks
See also: single-fork movie file
- movie poster
- A single visual image representing a QuickTime movie. You specify a poster as a point in time in the movie and specify the tracks that are to be used to constitute the poster image.
- movie preview
- A short dynamic representation of a QuickTime movie. Movie previews typically last no more than 3 to 5 seconds, and they should give the user some idea of what the movie contains. You define a movie preview by specifying its start time, duration, and its tracks.
- movie resource
- One of several data structures that provide the medium of exchange for movie data between applications on a Macintosh computer and between computers, even computers of different types.
- moving caret
See: single caret
- MPW
See: Macintosh Programmer's Workshop (MPW)
- MSAM
See: messaging service access module (MSAM)
- multicast address
- A hardware address that is shared by a subset of nodes on a particular data link"an Ethernet network, a token ring network, or an FDDI network. A multicast address is used to send directed broadcasts to this group of nodes rather than to all nodes on the data link.
- multichannel sound
See: stereo sound
- multimedia
- Combining multiple forms of communication to facilitate the transmission of ideas and information. These forms include text, pictures, video, sounds, music, and other types of data.
- multinode
- A node ID that an application or process can acquire that is in addition to the standard user-node ID that is assigned to a system when it connects to an AppleTalk network. Multinodes are used by special-purpose applications that receive and process AppleTalk packets in a custom manner instead of passing them directly on to a higher-level AppleTalk protocol for processing.
- multinode application
- An application that uses a multinode to receive DDP packets from and send them to another multinode or socket on an AppleTalk network. A multinode application typically implements custom processing of an AppleTalk packet. A multinode application cannot pass a packet on to a higher-level AppleTalk protocol for processing because a multinode is not connected to the AppleTalk protocol stack above the data-link layer. Multinode applications must include a receive routine to read in a packet's contents.
- multinode architecture
- A part of the AppleTalk protocol stack that implements a feature that allows an application or process to acquire multinode IDs. Multinodes allow a single system to appear and act as multiple nodes on an AppleTalk network. The multinode architecture is not connected to the AppleTalk protocol stack above the data-link level, and applications that use it cannot access the higher-level AppleTalk protocols, such as ADSP, from a multinode.
- multiple selection
- Selecting more than one item in a scrolling list, usually by Shift-clicking or Command-clicking.
- multiply-add instruction
- A type of instruction unique to the PowerPC architecture. Multiply-add instructions perform a multiply plus an addition or subtraction operation with at most a single roundoff error.
- multiprocessor computer
- A single computer having more than one processor to execute instructions
- multistyled edit record
- A TextEdit record that contains text with style information that can vary from character to character. A multistyled edit record contains a number of additional subsidiary data structures that support the text styling information.
- multitask
- To manage concurrent execution of more than one program
See also: cooperative multitasking, multithreaded, preemptive multitasking
- multithreaded
- Having more than one path of execution. For instance, one thread in a multithreaded program might handle user interactions, another thread might perform calculations, and yet a third might perform I/O
See also: thread
- multivendor architecture
- An AppleTalk feature that allows for multiple brands of Ethernet, token ring, and FDDI network interface controllers to be installed and used on a single node at the same time.
- Musical Instrument Digital Interface (MIDI)
- A standard protocol for sending audio data and commands to digital devices.
- mutual authentication
- Authentication of both ends of a communication link accomplished by exchanging a series of encrypted challenges and replies.