Smokey problem
 

So just wondering if anyone can tell me what this problem is.

I usually only drive from work to home which is only 15mins and all back country roads. Yesterday I had to go into the city so had a lot more driving. When I was stopped at a light I notice smoke coming up from my left front tire. Popped the hood Nd my power steering reservoir was boiling. Everything was extremely hot so I pulled over got a coffee and let it cool down before taking the highway home.
Pulled off the tire this morning and found the brake pad rubbing the rotor. Is it a calliper problem or brakes?

Any help would be great. Thanks.

Cause
 

Well for any readers I brought it in today and it was a seized calliper that was the problem. They are replacing the calliper and brake line. Recommended doing both but that's double the coin....

I bet it was the rubber brake line deteriorated on the inside holding the caliper together, seen that happen before.