Not just that aswell theres a few things you cant do until you have 50 posts, as quoted by Psycho4Bud.

1) Thou shalt not have a signature until 50 posts and 2 weeks account activation.

2) Thou shalt not post pics until 50 posts and 2 weeks account activation.

3) Thou shalt not give rep until 50 posts and 2 weeks account activation.

4) Thou shall notice when thee is blessed by a + sign along side "registered".