在下载有用的软件的时候常常因为网络或者其他原因突然断网，已经下载了一部分的软件又要重新下载，于是断点续传出现在网络上，大量的下载工具软件都支持这个功能，其意义就是可以继续上次没有下载完的文件下载，节省时间，不过断点续传功能需要服务器支持，现阶段的绝大多数服务器都支持断点续传。-Download useful software, it is often because of sudden network disconnection or other reasons, have downloaded the software, again, part of the download, then resuming in the network, downloading a large number of software tools to support this function, its meaning is that we can not continue to the last downloaded the file download, save time, but the server supports the HTTP functionality required at this stage the vast majority of servers support HTTP....