The amount of plugins available for the WordPress platform is staggering; there is just no way to try them all, or even to keep up with all the changes that go on. That being said, naturally some plugins stand above the rest, not necessarily because they are the best at what they do, although they certainly are competing for that title, but because they have reached the users, been thoroughly tested, and fill a need.
This chapter is dedicated to just a smattering of the marvelous plugins that are available. Even though the plugins covered here may seem like a lot, they represent only a drop in the ocean compared to what's actually out there. Along with using the information in this chapter you'll have to look around, and keep up with updates as well, to make sure you've got the best there is. Or rather, to make sure that you've got what you need. That's what it's all about, isn't it?
Oh, and before you get to it, sometimes you'll get warnings when trying out a plugin, being told that the plugin has only been tested up to this or that version of WordPress, and you have a newer one. That doesn't necessarily mean anything at all, other than that the plugin hasn't been tested with your particular version and/or the plugin author hasn't updated the plugin files. So don't be put off just because a plugin isn't tested with your version yet; set up a test blog and give it a go for yourself. Most plugins will work across versions, after all.