To remain stationary in traffic with a manual you have 3 choices. You can remain stopped with the clutch pressed in and the brake pressed, while you're in gear. The alternative is to press in the clutch, shift into neutral, then release the clutch. The only bad part about this is you have to quickly press the clutch back in and shift back into gear when the light changes. Or, you could shift into neutral, let the clutch out and release the brake and just put on the parking brake. If you don't have your foot on the brake or the parking brake on the car could start moving before you want it to. You should not release the clutch at a stop unless you are ready to go somewhere, if you release it without giving it gas it will buck and stall.