Anyone know what a blog tour is?

[ImperialBlether]

I've noticed a few writers bringing out novels have a blog tour. Does anyone know what it is?

Eg this:

It's where you do guest posts on a series of other people's blogs. It's useful for the writer because it means they get exposed to the readerships of all the different blogs and for the blogger because it gives them a blogpost with minimum effort.

Ohh okay, thanks. So would the publisher set that up?

I don't know what happens with big publishers with writers who actually have decent publicity budgets - I would think so. Smaller ones definitely do it themselves and I have seen people advertising, for actual money, the service of setting up blog tours for self published authors