If you know how to use keyboard and you know about keyboard shortcuts, you will increase your productivity on tasks, for example you know how to copy text or bold text etc.It will save your time if you are doing this with typing as selecting something from mouse with typing reduce your speed.
Ctrl + V or Shift + Insert
This is pasting command,These can be used to paste selected text from clipboard to selected aea.
Ctrl + C or Ctrl + Insert
This is copying command,These can be used to copy selected text to clipboard.
Ctrl + Z
This combination undo your recent changes, for example if you accidentally delete any thing , just give above command and deleted content will be there.
Ctrl + F
This is Finding key, this combination will always open a search box even if you type it in browser on pdf reader.
Alt + Tab or Ctrl + Tab
You can switch between open programs via this command in forward direction.
Shift + Alt + Tab or Shift + Ctrl + Tab
You can switch between open programs via this command in backward direction.
Windows + Tab
Windows Vista ,7 or 8 users can switch between open programs in full screen mode with this command.
Ctrl + Back space and Ctrl + Left or Right arrow
This combination can be used to delete whole world.
Ctrl + S
This will always use to save open document either PDF,word or any file.
Ctrl + Home
This command will move the cursor in the start of document.
Ctrl + Home or Ctrl + End
This command will move the cursor at the end of document.
Ctrl + P
This will show preview the open document. for example print preview.
Page Up and Page Down
It will move page forward to one page
It will move page forward to one page in internet explorer