PEAR, the PHP Extension and Application Repository, is quite misnamed—it contains neither extensions, nor applications! It does, however, contain many useful PHP components (that is, components written in PHP). These can help you do anything from authentication to internationalization to interacting with web services.
The biggest advantage that PEAR brings to the table is a great installer for these component packages, and any other packages created to the PEAR standard.
The PEAR package manager, found as the
pear command on most systems, is really
where it starts to get awesome.
Just like a system package manager (think APT, YUM, or ports), PEAR handles both required and optional dependencies. It can ...