In soccer, the long throw in is something that seemed to arise from soccer in the United States. It's not something you see often, if ever, in the English Premier League or La Liga. In those soccer leagues they'd rather throw the ball in to someone checking back to the thrower and then get the ball back and serve the ball into the box if needed.
As Cruyff said: "I always threw the ball in, because then if I got the ball back, I was the only player unmarked."
However, the long throw is very effective if you have someone who can really chuck the ball a long ways. Long throw ins then can become like corner kicks and are especially useful if you're losing and your team is desperate for a goal. In this video, Oguchi Onyewu helps his team score after his long throw in is flicked on and the person at the far post heads the ball in.
But sometimes opposing teams will place a man right in front of the person trying to do a flip throw or long throw in. Watch out, you don't want this to happen to you. See video below.