PHP is one of the world's most installed web scripting languages. Sites like Yahoo are adopting it as their standard. But, because PHP is not a precompiled language there is room for execution improvement. Enter the PHP accelerator. The following is a list of some PHP accelerators:

• Zend Accelerator
• Turck MMCache
• PHP Accelerator
• APC
• Afterburner

One of these should help you if your bottleneck is the actual execution of your PHP code. But what if you want to cache whole pages and serve up the cached pages? Well, you should look at jpcache. I used this for the first version of Geek(Wisdom).com with great success. Another approach to page caching is available in unearth. For an article about browser-side caching check out: PHP Cache Control.