68k
Refers to the 68000 Motorola processor or CPU, series of chips.

ADB (port)
The ADB (Apple Desktop Bus), is a cable/port standard on most 68k and eary PPC Macs (upto the blue and white G3 Macs). It allows you to connect the keyboard and mouse via through connectors.

Alias
Is a special file which points to the location of the original file/folder/disk. If you launch an alias, it will open the original file, folder or disk window instead. If you bin an alias, it will NOT delete the original.

Apple Events
Is the message language of System 7.5's Inter-Application Communications Technology (IAC), used by programs to communicate with other programs. It allows them to share data and commands. Applescript can use Apple Events to control the scriptable Finder and many applications.

Apple Menu
This menu is accessed via the Apple logo menu, on the very left of the menu bar. It's purpose is to allow easy access to utilities/programs and Control Panels. You can also place as many aliases of programs, in here as you like, for easy access.

AppleGuide
Is Apple's interactive help system, built into System 7.5 upwards. It can be accessed via the "?" icon on the top right of the menu bar, or by pressing the Help key. If you have enabled the AppleGuide Extension, then you can access all help guides, including Macintosh Guide, which is the Finder's help file - both located in the Extensions folder.

AppleScript
Apple's system level scripting software. It provides a way of automating complex or tedious tasks. You can even customise some user operations as well, see the "Automated Tasks" folder that is often installed into the Apple Menu.

AppleTalk
Is Apple's standard Macintosh network and printer communication language. It was the main and only standard on all MacOS's up to System 7.55.
Classic Networking, as it is now called, only allowed the use of AppleTalk as main network protocol, no other protocol could be used. For instance, Ethernet is converted into Ethertalk, which is an AppleTalk variant, before it is sent over the network.

Application
This term is just another descriptive word for 'program' (executable = computer code).

ATAPI
AT Attachment Packet Interface (ATAPI) is the description used to identify non-hard-disk devices used on the IDE/ATA channel. This includes CD-ROM, tape, and ZIP type drives. You could say that ATAPI refers to ATA drives that support removable media.

Bombed!
Is a common saying with Mac users. People usually say "My Mac just bombed!", when a System Error message appears, simply because this window displays a little icon of a bomb with a lit fuse on it!

Classic MacOS
Refers to system software from versions 1 to 9.2.2.

Clean Install
This refers to the type of System installation. The clean install option (from 7.5 onwards) let's you install the System Folder next to the original System that already exists on the destination volume. This will leave that original System intact but deactivated.

Clipboard
The Mac uses the Clipboard file (in the System Folder) to store data that has been copied or cut into memory. However, the data is lost when you restart or shutdown MacOS.

Clipping File
This is the product of dragging the on-screen selection, be it a piece of text, sound or image, from an application onto the Finder's desktop or disk, which immediately creates a Clipping file. This is only possible with drag'n drop capable applications.

Contextual Menus
Was introduced in System 8.0, and allows you to call up a little menu (whilst in the Finder) containing all the most common actions you are likely to use. It works only if you highlight an icon, window or disk, and then pressing the Control key and drag to the menu item - anywhere on screen.

Creator Codes
The creator code, actually refers to the program that saved the document/file. It is like a cattle brand, any file that has a programs' unique Creator code, launches that program when you double click on the it. It is also used to produce the file's icon, in conjunction with the file's Type code. All Creator codes (4 characters only) use upper and lower case characters, numbers, and even symbols.

Defaulted Icons
Means that the Desktop File for that Mac volume has become corrupted, and so, all icons on that disk have now assumed the System File's own standard set of default icons, namely a dog eared page icon (represents all document files), a rotated square with a hand pointing to it (represents any executable application), and default icons for System files, eg. Extensions, Control Panels, Control Strips and preference files. You will also see a dog-eared icon of a document, if you do not have the program that created that file.

Dirty Install
This type of System installation will update the current System Folder on the destination hard disk, with the newer System version. It will also leave all preferences and 3rd party Extensions & Control Panels as they were, as per the original System Folder.

Disk Drivers
Like PCs, Macs use drivers for it's hard disks, whether it is formatted via the Finder or another utility, it places the driver info into the rigid disk block for basic operational functions.

Desktop (The)
The desktop contains the menu bar, disk icons, background pattern, the trashcan and any icons you may have left lying around - it is basically the Finder's work space for organising icons and windows.

Desktop File
Is a disk based database for keeping information on icon and window positions, and what icons are used for which file or program. Without the Desktop file, all icons would revert to the System file's generic icon set.

Drag & Drop
This feature was introduced in System 7.1, it enables you to drag any document item, be it a bit of text, a picture, a movie or sampled sound, and literally drag and drop it either onto another document or onto the Desktop.

EIDE
Enhanced IDE, also called EIDE, is the term that Western Digital uses to describe its advanced drives that incorporate the performance improvements defined in ATA-2, along with several other refined protocols. EIDE has become a widely-accepted term in the industry, which would be great if not for the fact that it is used to stand for so many things, some of them completely different. For this reason, the term has been criticized - not least by Western Digital's competitors - for being confusing and vague.

File Sharing
Is the term used when you allow other users to have access to your hard disk on a network. Not only can you "share" an entire disk, but you can also "share" specific folders - which I believe you are able to do (share folders) from System 7.6 onwards. Sharing whole disks can be done in all versions of MacOS 7 onwards.

Finder
Manages the Desktop environment. When the Finder is placed in a folder, it "blesses" the folder with the familiar System Folder icon, to show you that this is the active System for this disk.

Firmware
This is the software or individual program modules, that are built into the Mac's ROM. Sometimes you can get Firmware updates (downloaded from Apple's web pages) to supplement the ROM. Apple's iMac and the blue & white G3 computers use Firmware updates.

Flashing "?" Disk Screen
This grey screen with a disk and a flashing question mark on it, immediately appears when the computer cannot find a valid System Folder to boot from. Macs can boot from; floppy disks, CD-ROMs or hard disks. Sometimes, even when you have inserted a bootable disk into the Mac, it may reject it, and still show the flashing question mark screen - this means that the disk you inserted is also invalid or non-bootable for your model of Macintosh. It may have a System Folder on the disk, but the computer doesn't recognise it, because the System Folder itself isn't been "blessed" with the normal System Folder icon - this is because there is no recognisable Finder and/or System file in it.

Flashing "X" Disk Screen
This grey screen with a disk and a flashing "X" on it, immediately appears when the computer tries to boot from an invalid System Folder. An invalid System, is one that was created for a different model of Macintosh - you see, each System file is built (during the installation process) specifically for that particular Macintosh, and cannot work on a different model of Mac. Or, that System is so corrupted that it is now invalid, as a bootable volume.

Forks
This term refers to the Resource and Data Forks, these make up all Mac files. Most files comprise of 2 forks, however each fork is stored on disk as individual files. You will not be able to see them ordinarily in MacOS, unless you use a file editor, such as ResEdit.
The Resource Fork contains program code/graphics, and icons, while the Data Fork contains any data, text or graphics for documents.

FTP
An ftp site is a server which has an Internet connection and uses the File Transfer Protocol (an agreed upon standard for transferring files using the TCP/IP protocol) to let you log on and download/upload files.
Servers can be Macintosh computers, MS-DOS machines, or UNIX based PCs or workstations. Limits, such as the number of users logged on, can be placed on an ftp site. Obviously, the more memory and processor speed a machine running as an ftp site has, the better able it is to handle more users, more file transfers, and so on.

Happy Mac Screen
This screen always appears right at the beginning of the System startup. It is a grey screen with a little pic of a smiling Classic Macintosh in the center. This indicates that all is well with the Mac (computer hardware diagnostics, and the System Folder is OK) - in emulation, all this means is that emulation is given a green light for booting up.

HD
Stands for hard disk. This is a piece of hardware that all modern computers use to store data onto. Hard disks are measured by capacity, either in megabytes or gigbytes.

Hard Disk Driver
Is the bit of information stored in the Rigid Disk Block, on a hard disk - all Mac hard disk formatting programs create this so called "driver" when it initialises the disk.
You can see which driver has been used for any disk, by highlighting the hard disk icon and pressing Apple+i, for the Get Info window. Look in the "Where" field, and it will give some details of where the disk is on the SCSI or IDE chain and the version of the driver that was used. In emulation, the main boot disk is called an AmigaDevice or AmigaFileDisk.

HFS & HFS+ (Hierarchical Filing System)
HFS/HFS+ is the Macintosh's only, filing system for hard disks. HFS Standard, as Apple likes to call it, was originally created for small (20 to 500mb) hard disks, and is limited by the number of blocks it can have on any partition. Meanwhile, HFS+/HFS Extended, is an improved version, allowing smaller block sizes for very large hard disks (1gig upwards), performance increase and better error handling.

IDE/ATA
The original, base specification for the family of interfaces described in this section is called both IDE and ATA. The name IDE is the more popular of the two, even though it is misleading since it stands for integrated drive electronics which refers to putting the logic board with the hard disk much more than it has anything to do with the interface. The more correct name is ATA or AT Attachment, which defines the standard interface.

The original IDE/ATA standard defines the following features and transfer modes:
Two Hard Disks: The specification calls for a single channel, shared by two devices that are configured as master and slave.
PIO Modes: ATA includes support for PIO modes 0, 1 and 2.
DMA Modes: ATA includes support for single word DMA modes 0, 1 and 2, and multiword DMA mode 0.

Initialise
This term refers to high level formatting of a hard disk, usually via the Finder or utility.

LUN
Stands for Logical Unit Number - it is a number used to uniquely identify and address a subsystem of a SCSI device. Usually it is not necessary to set the LUN, since most SCSI devices are single units. A SCSI peripheral that has LUNs are optical disk/CD-ROM juke boxes, and multiple custom hard disk tower RAID systems, all these have many drives in a single case.

MacBinary
Is an archive file type, but with no compression. It is similar to HQX, except that it is not ASCII encoded, instead it combines the two forks (resource & data) into one file. This makes the Mac file safe from corruption when it is transferred over to alien filing systems, ie. PC or Amiga formats.

MacOS
Stands for "Macintosh Operating System", ie. System 7.5.

NU-Bus
Is an old expansion slot type, used in all 68k Macs and some early PowerPC Macs.

Permissions
This actually refers to who owns files/applications under MacOS X. All files and folders have a permission setting, and these settings come in three main groups; Owner, Group and Others. The Owner is the user who has main rights to this folder or file, and he/she can set it so that only he/she can access the file/folder. Those groups have four settings; Read & Write, Read Only, No Access for files and folders, and Write Only is for folders only.

PICT
PICT is Apple's standard image file format. It is capable of holding 2-24bit colour pictures, as either bitmap or outline graphics (object orientated drawings).

Power Macintosh/PowerPC (PPC)
Power Macintosh refers to the PowerPC range of Macintoshs, that are currently being sold today. PowerPCs are RISC (Reduced Instruction Set Computer) based CPUs, these are capable of extremely high speeds.

PPD
Stands for Postscript Printer Description file, this can only be used with Postscript printer drivers, such as Laserwriter 8. They usually live in the Printer Descriptions folder, in the System/Extensions folder.

PRAM
Stands for Parameter RAM - this a tiny bit of memory that stores vital information, ie. the Startup Disk Control Panel setup, virtual memory settings, monitor and sound settings. Sometimes, this memory gets corrupted, so what you do is, you 'zap the PRAM' - to delete it's contents by a keyboard combination, see Keyboard Shortcuts for more info.

Printer Fonts
This actually refers to the Postscript Font files that are supplied with it's screen (bitmap) font, which are kept in a suitcase file(s). Printer fonts are exactly that, fonts that are downloaded to the printer so that the text in any document can be rendered to any size and rotation they were set to.

The difference between TrueType and Postscript printer fonts is that you can print out any character or words (from a Printer font) that have special effects applied to them, eg. skewed and rotated. This is not possible for TrueType, as it can only be printed "as is". However some programs get round this by converting the TrueType font to postscript before it is rendered to paper.

RAID
RAID stands for Redundant Array of Independent Disks. It is a way of linking several drives together so that they behaved and appeared as one large capacity drive.

There are a few options for setting up a RAID array. The two most common (range from RAID0 to RAID5) options are RAID Level 0 (Striping) and RAID Level 1 (Mirroring).

Striping increases data throughput to and from the member drives, by using all the drives to split up the file over all member drives. Mirroring uses dedicated hard disk members to simultaneously write files to both disks, basically making a backup of the main server RAID disk.

To find out more on RAID technology, there is a FAQ on FWB's web site: www.fwb.com.

Rebuilding the Desktop
This often used phrase in the Mac world, means you are recreating the Desktop Database files that hold the entire icon sets for all the documents on the disk you're about to rebuild. You do this by holding down the Apple+Option keys (and keep them held down) during the very last part of the bootup procedure. Then the Finder will ask if you want to Rebuild the Desktop for each locally mounted disk that has mounted. You can also invoke the Rebuild requester when you insert any removable disk, of course you still need to hold those keys down before it is mounted on the Mac's screen.

Restart
Is the Mac's terminology for a warm or cold bootup, into MacOS.

Sad Mac Screen
When you have a very hard crash, or something on the SCSI chain is not co-operating with the Mac, this screen will appear right at the beginning of the start-up procedure. The screen will be black, with two lines of white hexadecimal code under a little pic of a classic Mac with it's eyes crossed and mouth turned down, in the center of the screen. This hex code is produced by a real Mac's internal diagnostic routines, should something in hardware prove fatal. Emulation Notes: this will never happen in emulation, simply because Amigas have a totally different hardware design, and therefore cannot be diagnosed, and so this is skipped in emulation.

Safe Boot Mode
Also known as Safe Mode, it starts up Mac OS X (v10.2 or later) as usual, except it does a few of maintenance proceedures before loading into the Finder. These are:
• It checks and repairs the startup volume - this may take a while when booting up.
• It loads only required kernel extensions (some of the items in Hard Disk:System/Library/Extensions).
• It runs only Apple-installed startup items (some of the items in /Library/StartupItems and /System/Library/StartupItems - and different than login items).

Invoking the Safe Boot Mode allows you to work around boot issues caused by incompatible software or directory damage on the startup volume. Note that booting up in Safe Mode can take several minutes before you are presented with the Finder, because it is checking the hard disk directory, and depending on the size of the hard disk and the extent of repairs required, the time may vary a lot.

Features that don't work: Certain Mac OS X features do not work when you are started up in Safe Mode. For example, you can't use DVD Player, capture video in iMovie, use an AirPort card, use some audio input or output devices, or use an internal or external USB modem. Reboot when you have finished in the Safe Mode, to return to normal operation.

Screen Font
A screen font is a bitmap image of a font at a particular size (usually 9,10,12,14,18,24). These files normally live inside a suitcase file, along with other styles of that specific font family, ie. roman, italic, bold or bold-italic.

SCSI
Small Computer System Interfaces - is an industry standard interface for plugging in many peripherals onto a single computer, by daisy chaining them. There are currently three versions: SCSI1, SCSI2 & SCSI3 - and some very fast off-shoots: Wide SCSI, Ultra SCSI & Ultra Wide SCSI.

Shutdown
This menu item will remove all active temporary files, quit all open programs, and prepare the Mac for powering off.

SMIs (Self Mounting Images)
SMIs are really a special kind of disk image, it always has a application with a filename prefix of ".smi", this program will load all the "parts" and merge them together to create a fully accessible 'virtual disk' on your desktop.

Startup Volume
A Startup Volume is any partition or disk that has a valid (a System that works) System Folder, to boot from. This can be easily seen in the Startup Control Panel, as it will display all local disks that have a active (has the custom System icon on it's folder) System Folder on them.

Stuffit
Stuffit is probably the most common compression type on Macs at the moment. It is commercially available as Stuffit Deluxe, also appears on the internet as a shareware program called Stuffit Lite. All Stuffit files appear with a 3 character dot extension ".sit".

Suitcase
Is a special type of folder, which only allows one type of system resource to be stored in them, such as screen fonts (including Truetype), keyboard layouts, sounds and desk accessory files.

The System Folder
Contains all the elements that the Classic MacOS needs to operate correctly. You could take out all of the folders and extraneous files in the folder if you like, except the System, Finder and any System Enabler files, and it should still work.
Usually this folder contains: the System file, the Finder program, Extensions folder, Control Panels Preferences folder, Startup Items Folder, Shutdown folder by default.

Three Finger Salute
I know, this sounds like a "up-yours" type of gesture, but it isn't! Actually, what it refers to is the number of keys used (three in all) to reboot the Mac, eg. when a freeze or whatever has occurred and you need to restart the Mac again. The keys in question are: Apple + Control + Power key.

TrueType
Was introduced by Apple in 1990, just before System 7 was made available, it is a scalable font format that can be used at the System-wide level, and is mainly used for display and printing purposes. The only practical difference between TrueType and Postscript fonts, is that you cannot print Truetype fonts that have been rotated or have any special effects applied to them.

Type 1 Fonts
Are Postscript outline font files, based on Adobe's Type1 format.

Type Codes
Type codes are unique codes for all the different kinds of data files that reside on your hard disk. All Mac files have Type codes. The Type code also helps the program that opens the file, by telling it what kind of file it is, eg. whether it is a JPEG file, word processor file, plain text file, or an application/program - which always has the Type code APPL on them.
All Type codes (4 characters only) use upper and lower case characters, numbers, and even symbols.

Virtual Memory
Is a method of increasing memory (RAM) available to MacOS and applications by creating a file on your hard disk that stores segments of program code that are not used. Note that virtual memory is much slower than real RAM.