One of the things that amazes a lot of new users to Linux is how flexible the clipboard is. It's one of the many features of Linux that I've come to depend upon greatly. Without it, life could go on, but it would be much, much more difficult.

The first thing to know is that the Xwindows clipboard is what is commonly known as a "two level" or "two layer" clipboard. In comparison, the clipboards used on MacOS and Windows are only single layer. This means that they can only hold one thing at a time. A two layer clipboard can, as you can obviously guess, hold two separate items, one in each layer. The advantages of this are as interesting as the methods by which each part is accessed and used.

The first layer is your typical copy and paste layer, accessed and used via the ctrl-c, ctrl-v, and ctrl-x key combinations.

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