iTunes has completely vanished from my PC!

Help please! Just turned on my PC and iTunes has disappeared off it - the Music Library is still there with all the content including recently downloaded music, but the shortcut on the toolbar to iTunes says the programme cannot be found, and the desktop icon has completely gone. It does not appear in my list of all programmes either.

Can I just reinstall iTunes, and will my music content then sync with it? And does anyone know how this could have happened?

Thanks.