请问Capture里面Part和Symbol是什么区别？

Libraries are files that contain reusable part data. They contain parts that you can place as instances on schematic pages. Libraries contain a variety of symbols (such as power symbols, ground symbols, and so on) and title blocks that you can reuse in your projects. The relationship between the library and the parts and symbols it contains is similar to the relationship between a schematic folder and its contents. The contents of the library move with the library and are deleted with the library.

在Capture里面建立了一个library，然后可以“New Part”、“New Symbol”。

大家说说Part和Symbol的区别?

thx