All of these keyboard shortcuts can be used in any Microsoft Office application, and some may also be used when surfing the Internet.
Here are the shortcuts that I use the most:
CTL+C - copy selected text
CTL+X - cut selected text
CTL+V - paste selected text
CTL+ALT+V - paste special (really useful in Excel)
CTL+Z - undo
CTL+Y - redo
CTL+A - select all (text in a document, cells in a spreadsheet, whatever)
CTL+Home - go to top of document
CTL+End - go to end of document
CTL+S - save
ALT + TAB - switch to a different window
Print Screen - to get a screenshot (works best if you have software like SnagIt)
CTL+ALT+Del - open task manager
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