What does ~ mean?

Can be used to mean about/circa e.g. ~£1,000

It's a tilde

see here

https://en.wikipedia.org/wiki/Tilde

I use it to mean 'about' or 'approximately'. Not sure if that's its proper usage though.

It's an approximation sign, i.e. ~ £20 etc

Presonally I use it to indicate a destructor in a class ?

I've also seen it used on forums to denote drooling, or something sexy.

eg: David Tennant~~~ ?

Thanks guys. We were pretty sure it was being used incorrectly in a document, but weren't sure what you SHOULD do with it!

It was the least annoying punctuation mark I could have after my user name ?

<geek> I do use it to mean "approximately" in a scientific context, e.g.

~ 1N HNO3 (about 1 Normal Nitric acid) <geek>