What does it mean to “do something like a girl”? When did ‘like a girl’ become an insult?

We applaud the Always campaign which says that:

“Using #LikeAGirl as an insult is a hard knock against any adolescent girl. And since the rest of puberty’s really no picnic either, it’s easy to see what a huge impact it can have on a girl’s self-confidence.

We’re kicking off an epic battle to make sure that girls everywhere keep their confidence throughout”

Here’s the Always video for the campaign: