edis是一个key-value存储系统。和Memcached类似，它支持存储的value类型相对更多，包括string（字符串）、list（链表）、set（集合）和zset（有序集合）。-Redis is an open source, advanced key-value store. It is often referred to as a data structure server since keys can contain strings, hashes, lists, sets and sorted sets.