Copy items to the Office Clipboard

The Office Clipboard can hold 24 items. To place an item in the Office Clipboard task pane, select the text that you need to copy. On the Home tab, in the Clipboard group click Copy or press CTRL + C. To turn on the Office Clipboard, on the Home tab, in the Clipboard group, click the Clipboard Dialog Box Launcher.

This will place the item in the Office Clipboard pane. It will also show the program from where you copied (E.g., the Word icon will appear if you had copied from Microsoft Word, the Excel icon will appear if you had copied from Microsoft Excel and so on.)
You can also copy images and these items will also appear in the Office Clipboard task pane.
Once you had finished copying 24 items and if you perform a copy operation then it will be present on the top of the list and the last item in the list will be removed to give room to the newly copied item.