Taken straight from the Memcached website, "Memcached is a high-performance, distributed memory object caching system". In other words, Memcached helps you increase application perfomance by caching data in memory. Using Memcached to load data instead of a database or file system can have a major impact on your applications performance.

Implementing Memcached to improve your application's performance can be done fairly quickly without using Zend Framework. If you're just wanting Memcached, you don't necessarily need Zend Framework. On the other hand, if you're using Zend Framework but you're not using Memcached, this will help you get things going. But whatever your situation: If you're not already using Memcached, start tomorrow.

Find out how you can easily implement Memcached using Zend_Cache at A.J. Brown's blog post: "Memcached in PHP Made Easy With Zend Framework."