This is a list of the software which I use at home or work almost every day. Most of this is freely available, though a few commercial products are here too. I write software for a living, so don't be afraid to go out and buy commercial software when it fits your needs! Just realize that there's a lot of free (or very cheap) Macintosh software around that may do just what you want. Browsing the HyperArchive can be a good place to start; Apple's on-line software guide might also be useful.
Operating System. Most people don't think much about their operating system, and they shouldn't have to. A good operating system, at least for a desktop computer, works behind the scenes. Mac OS (now at version 9.2.1) comes close to this ideal; most of the time, it's easy to forget that you're working with an operating system at all. Remember: if you need to think about manipulating the files on your disk, and not their contents, there's a problem. No system so far eliminates this entirely, but the Macintosh can come close. Mac OS X (currently at version 10.1) is a little more foreign to me, but Apple is working hard on it as well.
Tool Bar. If you're like me, you shudder when you hear those two words. Real Macintosh software doesn't use tool bars! Or toolbars, for that matter. (Other software developers, are you listening?) But I've found one application-bar (or "dock") to be not only very useful, but also small and cheap. Malph, by Nitin Ganatra, holds application icons for you so you can launch them (or switch to them) with a single click. It's smaller than the built-in Launcher, shows not only the preconfigured applications but other running applications, and you can drag a file onto an application icon to open it. It even slips to the top when you drag the mouse to a corner of the screen. Very, very handy, and a great timesaver.
Word Processing. My word processor of choice for many years has been WriteNow. Unfortunately, it's been sold to a series of owners and languished in recent years (the last update was in 1994). The current owner is The Learning Company. Though it's not as full-featured as the goliaths, it does almost everything I need while remaining very small and blindingly fast. (Remember the days when word processors on a Mac SE ran faster than you could type?) It's a great program to use on a PowerBook, because it does almost no disk access during typical use. It's also quite cheap these days. However, since it's effectively no longer supported, I've recently begun learning Nisus Writer, another great Mac-only word processor. It's considerably more complex than WriteNow, but it's also much more powerful. (My wife prefers WordPerfect.)
Drawing. My favorite drawing program is LightningDraw GX, from Lari Software. It seems to be targeted at home illustrations (read: measurements don't have to be 100% precise), but it does that job very well. QuickDraw GX has some amazing capabilities and you can really show them off with this program. Of course, it requires QuickDraw GX (included in MacOS, but a separate install). Unfortunately, an update which runs under MacOS 8.x (with its non-GX printing) has been repeatedly delayed, though their web-oriented version, LightningDraw/Web, works as a stopgap. A good bitmap-oriented program is ColorIt!, from MicroFrontier. It's not as powerful as PhotoShop, but it's reasonably priced.
Finance. Even though Intuit seems to be slowly abandoning the Mac market, at least on the business end, I'm using Quicken for my home finances. I continue to use Quicken 98, as there don't appear to be any new features in Quicken 2000 and it's gotten lukewarm reviews. Yes, you can turn off the toolbar. (I don't recommend MacInTax, though I may try it again this year; I found some problems with the 1998 version, and Intuit's support is incredibly poor.)
Spreadsheet. I'm back to using AppleWorks after several years of working with Adrenaline's Numbers and Charts. Their spreadsheet was based on OpenDoc, a really cool technology idea from Apple, but one which unfortunately never took off in the marketplace and was recently discontinued (sigh). Luckily, Adrenaline's Charts SE software works without OpenDoc.
Database. It's old. It's not exactly a database. But it works OK for me. HyperCard, from Apple (well, Claris now), hasn't seen a major update in years&emdash;a lot of years. Still, it's a good semi-structured place to put useful information which you might want to search, like books, records, and the like. I wish Apple were still bundling the full version of HyperCard with their computers; it would be another compelling reason to buy Macintosh computers. Sigh. (I'm still looking for a real relational database for the Macintosh that is powerful and supports a reasonably good user interface; I've been spoiled by INGRES and RDB on the VAX.)
C compiler. CodeWarrior. From Metrowerks. 'Nuff said. Seriously, this is probably the best choice for a PowerPC C compiler right now; the latest release improves code generation, though it's still not perfect (compilers never are, I guess). You may want to consider using Apple's MrC compiler if you're really concerned about speed, especially when working with numerical algorithms.
Debugger. MacsBug, from Apple. Yes, it's low-level. OK, it's cryptic. No, there's no source-level debugging. But I write a lot of drivers, and it works best for me.
Text Editor. Despite some quirks, CodeWarrior is my current choice here too. The editor and project manager are tightly coupled, it's plenty fast on the Power Macintosh G3, and it feels like a real Macintosh program. On the other hand, BBEdit, from Bare Bones Software, is also a great editor, and I've only barely begun to learn how to take advantage of its power.
Compression and Decompression. I've got to start with StuffIt, from Aladdin Systems. Everyone, and I do mean everyone, who uses a Macintosh should have at least the free StuffIt Expander. And seriously think about buying the full version, not just the inexpensive DropStuff. It's worth it for the ability to easily work with archives, even if you don't use the automatic file compression features. The contextual menus work very well with MacOS 8, and I like the ability to double-click an archive and have it open as a window in the Finder.
Backup. I've finally switched from Dantz's DiskFit Pro, which I still consider a great single-machine backup program, to Retrospect, so that I can back up all of our computers across the network to tape. I highly recommend either of these programs. Dantz is an excellent company with a long history in the Macintosh market.
Resource and File Type Editing. How can anyone get by without ResEdit, free from Apple? It may be a clumsy tool when changing file types, but it's great for editing icons and strings, changing command-key equivalents for menu commands, or quickly peeking at code. If you need more power, Resorceror from Mathemaesthetics is the only choice.
Screen Saver. OK, these days you don't really need a screen saver. Monitors automatically shut off when the computer's idle (at least, on newer systems). But sometimes you just want something to stare at on screen. DarkSide of the Mac provides you with a collection of screen savers which, while they may not match the artistic quality or commercial licensing of the commercial ones, have the great benefit of being free. (The latest version of Darkside is shareware; please consider purchasing it to help support the author's cooking habit.)
Fax Software. While my USRobotics modem came with bundled fax software (MacComCenter), I just wasn't happy with it. When I heard that Supra sold their FAXcilitate software even if you didn't have a Supra modem, I bought it immediately. While it's not supported on non-Supra modems, it works fine on mine, and integrates very well into MacOS. [I haven't tried it with MacOS 9 yet, though.]
Sound Recording. I've used MicNotePad Lite on a few occasions. With a PowerBook, it's a convenient way to record a meeting while being able to participate in active discussions. (Taking detailed notes keeps you in the background, a good strategy if you prefer to be mostly ignored during meetings.)
Encryption. If you have something to say, consider saying it in private. PGP is the king of the encryption hill. Ever sent an embarrassing mail message to the wrong person? Did you know that any electronic mail you send which bounces may wind up being read by your postmaster? In fact, it's all accessible to the administrator of every machine between you and the recipient. Think about it. You can get my PGP key when you're ready. (I'm considering switching to SafeMail, from Highware, though; since PGP was purchased by Network Associates, their support has been lousy.)
Virus Checker. Disinfectant is free, powerful, and detects all the known Macintosh code viruses. (It is not effective against Microsoft products, unfortunately.) I don't recommend any of the commercial products unless you're forced to use Microsoft software.
Reading Mail. I've begun to use Mailsmith, from Bare Bones Software, the makers of BBEdit. It shows great promise, especially with its powerful filtering and searching capabilities, though it's not the fastest mail client. Bare Bones has been doing a good job of improving it over the past year. My wife uses Eudora Light, from Qualcomm. It works fairly well, though its interface is not exactly intuitive or Macintosh-standard. Still, it's stable and free. The Pro version, which I still use at work, adds more filtering and the ability to handle multiple accounts (Mailsmith excels at both of those).
Logging On. My favorite terminal emulator is VersaTerm, from Synergy Software. It does a great job of emulating a DEC VT220, which is the closest I've seen to the perfect terminal. (Its keyboard was better than even the best Mac keyboards. Ah, nostalgia.) If you don't need a perfect VT220 emulation (or DG D200), consider NiftyTelnet instead, which will do a decent VT102.
Reading News. I use MT-NewsWatcher, a multithreaded newsreader for the Mac. I'd used the original NewsWatcher for years, so this version is familiar while more powerful. Simon Fraser has done a good job of adding features to John Norstad's code while retaining the polished mix of MacOS look-and-feel with quick-and-dirty command shortcuts.
Viewing Graphics. Got a JPEG file you want to see? Or a GIF? Pull them into JPEGView, by Aaron Giles, and you'll see the best approximation your screen can display. If you've got 24-bit color, it's a fast viewer; if you don't, it'll use dithering as good as any I've seen. And it's free (technically, it'll cost you one postcard and a stamp). Get it today. (Unfortunately, it doesn't handle progressive JPEGs; Jade is a free alternative for this.) For movies, or to see even more graphics formats, or for sound, get QuickTime today. (If you've got a Mac, you already have it, but don't forget to download QuickTime 4 if you haven't already.)
Browsing the Web. I don't like Microsoft. I don't like Netscape. They're both arrogant and pushy (do not play well with others). I used to use Apple's Cyberdog, but it's no longer supported (sigh) so I've gone back to Netscape. I'd welcome other alternatives; iCab looks interesting.
Authoring Web Pages.I've begun to use BBEdit, but haven't been doing much on my web site lately. My wife has a copy of Claris Home Page. It works pretty well, though it's missing site management features (so simple changes like moving a page require a lot of error-prone manual changes). I'm not doing anything complicated, of course. Unfortunately, like many Claris products these days, it feels rather like a PC product. Do we really have to put up with poorly-hyperlinked help text instead of a decent help facility? There isn't even balloon help. I'm disappointed. (Version 3 is also very slow, at least when editing tables on a Power Mac 7200. Sigh.)
Debugging Your Internet Link. Sometimes the internet just isn't working. Consider WhatRoute as one of your tools for finding out why. It can check whether a remote host is responding, trace the link between your computer and another, and help you find out where a system is hooked in and who's in charge of it.
Basic moving parts. I'm listing several dissimilar games here because they all involve little graphic elements moving around. I first played Daleks on my Mac 512K, and Classic Daleks is a good modern version of this Doctor Who-inspired game. Chrysanthemum is a very nice game which is hard to explain; think of sorting flowers into Tetris-style blocks. Skittles is a fun game involving pieces which you eliminate by guiding them to merge with other pieces of the same color. One of my wife's favorite games, JewelBox, is a connect-three style game in the same vein.
Strategy. My wife got me temporarily hooked on Civilization II, which is an enjoyable game in which you try to conquer the world, or at least be first to another planet. At the moment, I need to finish Riven, which my parents bought me. It encouraged me to finally finish Myst, as well as encouraging me to buy some good speakers. Oh, and I've enjoyed both SimCity Classic and my just-purchasd copy of SimCity 3000.
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