Formula - How to clear extra spaces or wild characters in text?

Two formulas can be used for this purpose:

1. Trim ( )
   It removes all extra spaces from the target cell.
   e.g. all spaces before and after the text and more than one space in between words.
2. Clean ( )It removes wild and non-printable characters from the target cell.
   e.g. non-readeable characters that come from extarnal data copying or opening a non-recognizable file.