Windows 操作系统的注册表包含了很多有关计算机运行的配置方式，打开注册表我们可以看到注册表是按类似于目录的树结构组织的，其中第二级目录包含了五个预定义主键分别是：HKEY_CLASSES_ROOT，HKEY_CURRENT_USER，HKEY_LOCAL_MACHINE，HKEY_USERS，HKEY_CURRENT_CONFIG。-Windows operating system registry contains a lot of information about the computer running configuration, open the registry we can see that the registry is a directory tree structure according to a similar organization, in which the second-level directory contains five predefined master keys are : HKEY_CLASSES_ROOT, HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE, HKEY_USERS, HKEY_CURRENT_CONFIG.