There are following types of Cache we can implement to make our website
- Super Faster
- Increase search engine ranking
- Increase performance
- User friendly
Page Cache:Page Cache refer to Caching pages in html file. and serve cached file to user on recurrent request.
Object Cache: WordPress inbuild have a feature of caching DB queries is called object cache. The object cache is non-persistent cache. It does not maintain state. means it will reside in memory only for a duration of a request. Object cache will get stored for a period of time until persistent cache plugin not installed in site. If persistent cache plugin not installed in the site it stored in
Database Cache: Similar as of Object Cache we can Cache other DB queries with Database Cache.
Opcode caching: It refer to caching compile PHP code. PHP is an object oriented programming language and it get compiled by PHP compiler on each request Opcode cache is caching compile PHP file code.
You can explore server-level cache options in details from here