[1.1 PHP简介](1.1PHP%E7%AE%80%E4%BB%8B.md) [1.2 PHP7的改进](1.2PHP7%E7%9A%84%E6%94%B9%E8%BF%9B.md) [1.3 FPM](1.3FPM.md) [1.4 PHP执行的几个阶段](1.4PHP%E6%89%A7%E8%A1%8C%E7%9A%84%E5%87%A0%E4%B8%AA%E9%98%B6%E6%AE%B5.md)