Question : What does the "<<" operation do?

I'm sure this is a novice question, but I have some PHP code I'm converting and it has the "<<" operation in it. I've never seen it before and can't find it on google or through w3schools. Can anyone help? The code I have is like this:

return MyFunction(lon) + (x << (21 - val1))

Answer : What does the "<<" operation do?

Hi,

The answer is no.

Sorry,

- gurutc