个压缩归档实用程序。按照文件的时间、大小、类型(文件或者目录)、最后修改时间等进行筛选 能够把这些文件压缩，并添加适当的注释帮助辨认 能够添加校验值以确保复制和网络传输时不出错 保持备份时的目录结构以便恢复。-000 compressed archive utility. According to the document, size, type (file or directory), last modified time to screen these documents compression, and add the appropriate Notes can be added to help identify the checksum to ensure replication and network transmission time is not wrong to keep the backup directory structure to restore.