I thought when climbing, it is better to stay seated with proper form then it is to stand... I am knew to cycling, so when ever i climb i try to use a proper technique while staying seated. Pulling and pushing with both legs. When you stand you mostly just push. Am i wrong? Should i be standing when climbing.

I passed some dude the other day while staying seated when he was standing. He looked a a lot more tired then I. Of course i don't know how long he was cycling.

Should i sit or should i stand?