One part of the MySQL installation process is data directory initialization (see Section 2.10.1, “Initializing the Data Directory”). MySQL安装过程的一部分是数据目录初始化（参阅第2.10.1节，“初始化数据目录”）。During data directory initialization, MySQL creates user accounts that should be considered reserved:在数据目录初始化过程中，MySQL会创建应被视为保留的用户帐户：
'root'@'localhost: Used for administrative purposes. This account has all privileges, is a system account, and can perform any operation.：用于行政目的。此帐户具有所有权限，是系统帐户，可以执行任何操作。
Strictly speaking, this account name is not reserved, in the sense that some installations rename the 严格来说，此帐户名不是保留的，因为一些安装将root account to something else to avoid exposing a highly privileged account with a well-known name.root帐户重命名为其他名称，以避免暴露具有知名名称的高权限帐户。
'mysql.sys'@'localhost': Used as the ：用作DEFINER for sys schema objects. sys架构对象的DEFINER定义者。Use of the 使用mysql.sys account avoids problems that occur if a DBA renames or removes the root account. mysql.sys帐户可以避免DBA重命名或删除root帐户时出现的问题。This account is locked so that it cannot be used for client connections.此帐户已锁定，因此无法用于客户端连接。
'mysql.session'@'localhost': Used internally by plugins to access the server. This account is locked so that it cannot be used for client connections. ：插件内部用于访问服务器。此帐户已锁定，因此无法用于客户端连接。The account is a system account.该帐户是系统帐户。
'mysql.infoschema'@'localhost': Used as the ：用作DEFINER for INFORMATION_SCHEMA views. INFORMATION_SCHEMA视图的DEFINDER。Use of the 使用mysql.infoschema account avoids problems that occur if a DBA renames or removes the root account. mysql.infoschema帐户可以避免DBA重命名或删除根帐户时出现的问题。This account is locked so that it cannot be used for client connections.此帐户已锁定，因此无法用于客户端连接。