We are marking Twitter’s game-changing micro-blogging service’s fifth birthday by highlighting five significant charity landmarks that have transpired in 140 characters

Not that long ago, if you wanted to make a personal approach to someone, you wrote them a letter.

There’s nothing quite like a letter. It makes you feel special. It sounds as if it knows you, about things you’ve done, places you may have been, things you care about.

Well, I’ve just checked with a few people and apparently it isn’t me. According to my daughter I score “zero” on the cool-o-meter. So it must, therefore, be the world of charity.