A filter is a device that removes particles from a given liquid or gas. It includes a disposable medium for removing particles of specified micron sizes. Simply stated, a Strainer is also a filter; however, it uses a perforated plate or screen mesh to remove larger particles from a process stream.
The major advantage of a Strainer is that it is reusable.
There are three levels of straining a) coarse, b) medium, and c) fine.