Input mask for LibreOffice Calc cells

This is a wiki page. Be bold and improve it!

If you have any questions about the content on this page, don't hesitate to open a new ticket and we'll do our best to assist you.

Question:
How do I create an input mask for in spreadsheet cells in OpenOffice Calc?
Answer:
There does not seem to be such a feature that works out of the box. We can be done is work with several columns, with one column used for input and the next used for a computed value.