One goal can be the difference between winning and losing.
And when you get down to it, that goal can be determined by mere inches.
For instance, the ball's here, not a goal.
You know, if any part of the ball is still touching the line, it's not.
You gotta be able to see the green on the other side.
And with the linemen so far away it can be really hard to tell if that ball actually crosses the line, especially if it's in the air.
To eliminate any guess work for referees, for the first time at the World Cup FIFA will be using goal line technology at each match.
There's been so many times over the past handful of years that.
Balls, you know have been called in and they're not completely over the line and vice versa.
Balls that, you know they've called no goal and it's, it's actually gone in.
Here's how goal controls for these systems works.
14 cameras are mounted above the field, 7 at each goal.
They track the balls that fly through the air in real time.
If it crosses the goal line, the software program transmits a signal to the referee's watch within a second.
It claims to be accurate down to 5 millimeters.
And it's encrypted to prevent hacking.
As a forward it kinda, kinda of against it cuz, I mean, it could take away from some goals that may or may not have been in.
But I think overall for the game, I think it's a good, it's a good thing.
That's the biggest stage, and there's just so much on the line that you know just clear up those decisions.
Soccer enthusiasts hope technology doesn't change the spirit of the game.
I think the argument is just affecting the purity of the game and the flow of the game.
There's so much at stake especially at the highest levels.
But accuracy comes at a price.
Goal control system cost around $400,000 to install in each stadium.
In San Francisco, I'm Kara Tsuboi for CNET.com for CBS News