Hash, pound or sharp?

♯ = sharp sign (as used in music)
# = hash (Commonwealth English) or pound (North American English) sign; aka the number sign
They are not the same thing!

Forever vs For ever

There is a distinct difference between forever and for ever. The first word is an adverb, meaning continuously or persistently - "he is forever losing his wallet", "she is forever complaining". As two words, "for ever" is an expression meaning for all future time, or - more colloquially - for a long time.