As a rule, these "inits" do not take up RAM at startup, so leaving them in your "Extensions" folder will not increase the size of your system RAM allocation at startup. However, they must still be "active" (in the "Extensions" folder) at startup to be used/loaded. Some of them aren't even loaded at startup, but are needed later (such as shared libraries and documents which are loaded on an as-needed basis).
[There are exceptions to this "rule," such as when the System software or another init actually calls on a shared library and/or document at startup, but it's not vital to go into that here.]
SHARED LIBRARIES:
Also known as Dynamically Loaded Libraries. They are called "shared libraries" because they provide sets of common code which can be used by different applications, rather than each application having to contain the code within itself. They are loaded only as needed, not necessarily at startup:
窶「 PM AppleScriptLib (v1.2.2): provides native code AppleScript support. PowerPC native applications which utilize AppleScript need this. Obviously, if you use AppleScript, you also need this. Version 1.1 is installed by the latest system software; version 1.2.2 is installed by Apple Telecom 3.0.
窶「 ColorSyncLib 68k (v2.0.1): Code Fragment Manager file for the Color Sync software included with the LaserWriter 8.4 installation on 680x0 Macs.
窶「 DragLib: a shared library used by the Drag Enabler on PowerMacs. This was only necessary under earlier systems, and is no longer needed.
窶「 PM LibMoto: a third party shared library which accelerates mathematical operations on PowerMacs (see "MathLibMoto" below). This is the official Motorola release. It is slower on some operations than MathLibMoto, but is more accurate. It also conflicts with the GeoPort modem software, while MathLibMoto did not.
窶「 PM MathLib (v2.0.1): Provides PowerPC numerics routines for native applications. Installed with system update 7.5.1, but incorporated into the system in 7.5.2.
窶「 PM MathLibMoto: a third-party shared library extension written by a Motorola employee. It contains a PPC-native shared code library for floating-point math operations which is more efficient than Apple's own code. It is useless on 680x0 Macs, but on PowerMacs it will improve the performance of applications which use a great deal of floating-point calculations (such as rendering/ray-tracing apps, statistical software, and graphic imaging programs) as long as the applications are PPC-native. Also, QuickDraw 3D will gain some noticeable speed. On the other hand, word-processing, DTP, database work, etc. will gain very little from using MathLibMoto. Motorola has asked those distributing this extension to stop, because they have released an "official" version, LibMoto (see above).
窶「 NuQuickTimeLib.slb (v2.0.1): Code Fragment Manager file for the LaserWriter 8.4 installation on 680x0 Macs.
窶「 NuThreadsLib.slb (v2.0.1): Code Fragment Manager file for the LaserWriter 8.4 installation on 680x0 Macs.
窶「 PM ObjectSupportLib (v1.1): Provides services to allow applications to send and receive Apple Events that conform to the "object model"--e.g. □provides support for AppleScript on PowerMacs; some native applications require this library. Version 1.0.2 is installed by the latest System Software installer (7.5.3 "Unity"), but some Netscape installers install version 1.1.
窶「 "OpenTpt xxx Lib" files implement core Open Transport service on PowerPC machines. In particular, the "Lib" files below contain the modules and APIs for native PowerPC applications. They are needed on all PowerMacs for Open Transport to function.
o PM 窶「窶「窶「OpenTptAppleTalkLib (v1.1): necessary for native AppleTalk support under Open
Transport.
o PM 窶「窶「窶「OpenTptInternetLib (v1.1): necessary for native TCP/IP support under Open
Transport; if you are not using any TCP/IP (Internet-related) services, you can remove
this.
o PM 窶「窶「窶「OpenTransportLib (v1.1): necessary for basic (core) Open Transport functions on
PowerPC machines.
窶「 PM "Open xxx 68K Library" files are used for the 680x0 implementation of Open Transport. They are necessary on 680x0 Macs for Open Transport to function. They are NOT needed on PowerPC computers and will actually cause them to slow down, since they end up emulating 680x0 code when native PowerPC code is available. Thus, they should be removed from PowerMacs.
o 窶「窶「窶「Open Tpt ATalk 68K Library (v1.1): necessary on 680x0 Macs for AppleTalk
support under Open Transport.
o 窶「窶「窶「Open Tpt Inet 68K Library (v1.1): necessary on 680x0 Macs for TCP/IP support
under Open Transport; if you are not using any TCP/IP (Internet-related) services, you
can remove this.
o 窶「窶「窶「Open Transport 68K Library (v1.1): necessary on 680x0 Macs for basic Open
Transport functions.
窶「 OTGlobalLib: actually not a separate file, but part of the OpenTransportLib file. If OpenTransportLib or OpenTransportLibrary are not installed and you try to open the AppleTalk control panel, you may get an error message that OTGlobalLib could not be found.
窶「 PM PrintingLib (v8.4): provides native support for the LaserWriter 8.4 software.
窶「 QuickTimeLib: actually not a separate file, but a shared library which is incorporated into the QuickTime PowerPlug extension. On a PowerMac, some applications, such as Graphic Converter, will display an error such as "Can't find QuickTimeLib" if QuickTime PowerPlug is not installed.
窶「 SoundLib: actually not a separate file; a shared library which is incorporated into the Sound Manager extension (3.0 or later). Some applications, such as Sparkle 2.4.5, will display an alert like "Can't find SoundLib" if SoundManager is not installed.
窶「 PM 窶「窶「窶「ThreadsLib (v2.1.2): Provides native Thread Manager support for native applications (cooperative threads only). Provides additional information for developers on PowerMacs. Incorporated into the System or System Update 7.5.2 under System 7.5.3.
窶「 XTND Power Enabler: a Power Macintosh shared library system extension enabling native Power Macintosh applications to call the Claris XTND System. Only the interface library has become native, the remaining parts of XTND, like Claris XTND System remain the same 68K code.
DOCUMENTS:
Similar to Shared Libraries, these are used by the Shared Library Managers, and are not loaded into system RAM at startup:
窶「 PM "Open Tpt xxx LIbrary" files implement core Open Transport service on PowerPC machines. In particular, the "Library" files below contain the modules and APIs for 68K applications running in emulation. They are needed on all PowerMacs for Open Transport to function. They are used not only by non-native applications, but also by the System software, which is not yet fully native.
o PM 窶「窶「窶「Open Tpt AppleTalk Library (v1.1): necessary for 680x0 emulation AppleTalk
support under Open Transport.
o PM 窶「窶「窶「Open Tpt Internet Library (v1.1): necessary for 680x0 emulation TCP/IP support
under Open Transport; if you are not using any TCP/IP (Internet-related) services, you
can remove this.
o PM 窶「窶「窶「Open Transport Library (v1.1): needed for basic 680x0 emulation OT functions.
窶「 窶「窶「窶「Serial or Serial (Built-in) (v1.1) (formerly called "Serial Extension"): Configures the serial ports/allows the serial ports to be used by communications programs and Open Transport.
窶「 SNMP Macintosh Agent, SNMP MacTCP Agent, SNMP Manager, SNMP TCP/IP Transport (all v1.0.2): these files, along with the MacSNMP Client, were installed for SNMP support by the MacTCP 2.0.2 Installer. They are no longer needed if you have the latest version of MacTCP (2.0.6).
窶「 PM StdCLibInit: an Apple init installed by CodeWarrior 9. It is necessary in order to run the PPC-native version of the MPW shell.
COMPONENTS:
These are used by other apps/inits. They are loaded at startup, but they don't take up system RAM until they are called upon:
窶「 Apple Photo Access (v2.1): necessary only for KODAK PhotoCD access. Needs the Foreign File Access extension in order to function.
窶「 Audio CD Access (v5.1): necessary to listen to audio CD's in your Mac's CD-ROM drive. Needs the Foreign File Access extension in order to function.
窶「 AV Setup (v1.0): under 7.5.2, allowed the Sound & Displays control panel to talk to the Mac's hardware; also allowed control of the AppleVision displays. However, according to Apple, this component is no longer needed.
窶「 High Sierra File Access (v5.1): for CD-ROM's encoded in the High Sierra language (fairly rare nowadays). Needs the Foreign File Access extension in order to function.
窶「 Internet Config Extension (v1.2): used by certain Internet applications, such as Anarchie and Claris Em@iler; allows you to use standard preferences across all compatible applications. See documentation for details.
窶「 ISO 9660 File Access (v5.1): for CD-ROM's encoded in the non-HFS ISO 9660 standard (again, rare for the average user). Needs the Foreign File Access extension in order to function.
窶「 KODAK files: installed by some graphics programs (PhotoShop, etc.).
窶「 Macintalk 2/3/Pro (v1.4): part of the Speech installation, allows the computer to read text in human voices (2 and 3 require Speech Manager and the "Macintalk 2/3 Voices" files; Pro requires Speech Manager and the "Voices" folder in the System Folder with voice files installed); . Pro is for 68040 and PowerPC Macs; 3 is for 68030, 68040, and PowerPC Macs; 2 is for 68020 Macs and Macs running pre-System 7 system software. For more information on Speech, see the "Groups" chapter.
窶「 窶「窶「窶「SystemAV (v1.1): allows the Monitors & Sounds control panel to talk to the Mac's hardware; also used for audio-video input on the PCI Macs.
COMMUNICATIONS TOOLS:
These are used by communications apps. Again, they don't take up RAM, and don't affect your system until called upon:
窶「 Apple ISDN Telephone Tool (v1.0.2): for use with the Apple ISDN NuBus Card. This version is part of the Telephone Manager 1.1.1 update.
窶「 窶「窶「窶「Apple Modem Tool (v1.5.5): supports 115.2K and 230.4K connections on those Macs that support SerialDMA.
窶「 AppleTalk-DECnet Tool: used to communicate with servers running the VMS operating system from Digital (also known as VAX/VMS or Alpha/VMS). DECnet is a network protocol used by VMS to copy files, establish terminal sessions, etc. with VMS servers (similar to TCP/IP in the Unix/Internet world). There are a few rare emulators which use this file. If you are using one of them, you'll know. Most people nowadays use TCP/IP to communicate with VAX machines.
窶「 AppleTalk-LAT Tool: used to communicate with servers running the VMS operating system from Digital (also known as VAX/VMS or Alpha/VMS). LAT (Local Area Transport) is a non-routed network protocol used by VMS. It is used only to establish terminal sessions with VMS servers. There are a few rare emulators which use this file. If you are using one of them, you'll know. Most people nowadays use TCP/IP to communicate with VAX machines.
窶「 Claris Kermit Tool: necessary for Kermit file transfers under the ClarisWorks terminal program.
窶「 CRC TelePort TelTool: allows you to use the MegaPhone software with an internal Global Village Teleport Platinum modem.
窶「 DAL: an extension from System 7.0.1 that allows you to access databases on unix platforms that support the DAL (Data Access Language) protocol. Chances are, unless you have a DAL server ($4000 or more) and know how to set it up, you'll never need this extension. This extension was originally developed/ owned by Apple, but was later sold to another company.
窶「 Express Modem Tool: allows communications over the Apple Express Modem.
窶「 MacPAD: part of the MacX25 package, allows access to MacX25 servers using the X25 protocol. AppleLink is run over X25.
窶「 TCPack for AOL: allows you to access America Onlince over a direct TCP/IP connection.
窶「 Text Tool (v1.0.1): allows direct, uncorrected file transfers. Used to send files directly as text. Nearly obsolete.
窶「 TTY Tool (v1.0.1): provides support for a teletypewriter-emulation connection. Also provides an alternative to ANSI and VT-120 protocols when connecting to a BBS or for direct modem-to-modem connections.
窶「 VT 102: presumably allows your Mac, using compatible telecom software, to emulate a VT102 terminal.
窶「 XMODEM: provides support for transferring files using the XMODEM protocol.
CHOOSER EXTENSIONS:
These are extensions which allow access/connection to various types of networks, services, printers, etc. using the Chooser.
窶「 AppleTalk ImageWriter: a chooser extension for the AppleTalk ImageWriter dot matrix printer. This printer requires that AppleTalk be turned on.
窶「 CG Maker 1.1.2: a chooser extension which allows you to prepare a "Common Ground" document for distribution. Similar to the Adobe PDF Writer (below).
窶「 Color SW 2200 (v2.1.1): a chooser extension for the Color StyleWriter 2200.
窶「 Color SW 2400 (v2.1.1): a chooser extension for the Color StyleWriter 2400.
窶「 Color SW 2400 GX: a QuickDraw GX chooser extension for the Color StyleWriter 2400.
窶「 Color SW Pro (v1.5.2): a chooser extension for the Color StyleWriter Pro.
窶「 Fax Sender: a chooser extension which allows faxing from within applications using the Geoport modem.
窶「 Fax Sender GX: a QuickDraw GX chooser extension which allows faxing from within applications using the Geoport modem.
窶「 Genigraphics: a chooser extension which allows you to prepare files for Genigraphics service bureaus. Genigraphics is a computer graphics system which started in the late 70's. They have service bureaus which will take your Genigraphics files and convert them to professional quality prints and slides. However, in many industries, PostScript files have taken over as the dominant file format. This file is installed by MicroSoft PowerPoint and Office, as well as by Astound 2.0.
窶「 GlobalFax: if this driver is chosen in the Chooser, the "Print" command in applications will be replaced by a "Fax" command. If you would like to do occasional faxing, hold down the Option key as you select the "File" menu, and the "Print" command will temporarily change to "Fax."
窶「 GlobalFax GX: The QuickDraw GX driver for direct faxing. If this driver is chosen in the Chooser, the "Print" command in applications will be replaced by a "Fax" command. If you would like to do occasional faxing, hold down the Option key as you select the "File" menu, and the "Print" command will temporarily change to "Fax."
窶「 ImageWriter (v7.0.1): chooser extension used for the dot matrix ImageWriter printer. This printer is a serial printer, and thus does not require AppleTalk to be turned on (see AppleTalk ImageWriter, above).
窶「 ImageWriter GX: QuickDraw GX chooser extension for the dot matrix ImageWriter printer.
窶「 ImageWriter LQ GX: a QuickDraw GX chooser extension for the ImageWriter LQ.
窶「 LaserWriter 300 & LaserWriter 300/LS (v1.2): chooser extension to be used with the Personal LaserWriter 300, LaserWriter Select 300, and the Personal LaserWriter LS.
窶「 LaserWriter 300 GX: QuickDraw GX chooser extension to be used with the Personal LaserWriter 300, LaserWriter Select 300, and the Personal LaserWriter LS.
窶「 LaserWriter (v8.4): chooser extension for the LaserWriter, LaserWriter Plus, Personal LaserWriter NT/NTR, LaserWriter II NT/NTX, LaserWriter IIf/g, LaserWriter Pro, LaserWriter Pro 600/630/810, LaserWriter Select 360, Personal LaserWriter 320 and the LaserWriter 16/600. The latest versions of the LaserWriter 8 driver (8.3.4 and 8.4) are recommended for anyone using System 7.5.3 and/or anyone with a PCI-based PowerMac. Version 8.3.4 contains the LaserWriter driver only, and fixes problems with printing to a network printer or a dedicated print spooler. Version 8.4 is a full installation of the newest LaserWriter 8 package. It is PowerPC native (but works on 680x0 Macs as well), features single-pass printing, and includes new Print and Page Setup dialog boxes which work better with desktop printers. The installation also includes the latest version (2.0) of the Desktop Printing software. NOTE: the "Finder Help" extension is required for LaserWriter 8.4 to install properly. If you are missing this file, it can be found on Disk 2 of the LaserWriter 8.4 installation. Drag it to the Extensions Folder and then install again. NOTE #2: If you are using Open Transport, in order to print to a LaserWriter you need the Shared Library Managager, Shared Library Manager PPC (if you are on a PowerMac), and the appropriate Open Transport and Open Transport AppleTalk files for your machine (see "Shared Libraries" and "Documents" above).
窶「 LaserWriter GX: QuickDraw GX chooser extension for use with all printers supported by the LaserWriter driver.
窶「 LW Select 310: chooser extension for the LaserWriter Select 310. This is one of the few non-AppleTalk LaserWriters.
窶「 HP Accupage (1.08): a chooser extension used by the Hewlett-Packard ScanJet 4C.
窶「 HP LaserJet (8.2.1): a chooser extension used with HP laser printers.
窶「 MacX25 2-1.3: allows you to connect to a MacX25 server.
窶「 PDF Writer: a chooser extension which you can select to "print" (save) documents in the Adobe ".pdf" format (Portable Document Format) using the print dialog. The file can then be sent/copied etc. in a form readable by the Acrobat Reader (freeware) on anyone's machine, no matter what application created it. (Holding down the control key when selecting "Print..." from the file menu is the usual temporary shortcut, instead of using the Chooser). This is installed by PageMaker, Acrobat, and other Adobe products, and requires Adobe Type Manager.
窶「 PSPrinter (8.2.1): a chooser extension, originally developed by Adobe, used by some third-party postscript laser printers, such as the Texas Instruments line of printers. Also supports Apple-branded printers. In addition to the standard laser printer features, it also provides "virtual printer" support, allowing you to print to a PS file without having a printer connected.
MODEM FILES:
These are documents installed by various telecom applications/devices which are used to allow connections over various modems.
窶「 Modem LinkTool Personal documents: these files are used to connect over ARA using various modems. They do not show up in any startup manager utilities. However, they are stored in your "Extensions" folder and have the following icon:
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If you "Get Info" on one of these files, the "Kind" will be listed as "Modem LinkTool Personal document." When you use the "Remote Access Setup" control panel, the pull-down "Modem" menu will list these files and allow you to choose the modem you are using. For the most part, you can remove any of these that do not correspond to a modem you are using (or might use!).