noob mapping question

So I've just started learning out to do Hammer, learning the basics. This is a really noob question, but I haven't really seen anything on this in the tutorials I've been reading.

I'm assuming that there's a way to make, say, walls (I guess the proper term is brushes) to sort of...snap together? It's a pain to try to get them in the right place manually. I have to get the grid small enough so that there aren't any leaks and that I'm not overlapping the brushes too much. Also, is there a quick way to rotate brushes exactly 90 degrees or whatever you want?

If there isn't a way to do these two things, I would like some tips on them. Thanks!

Walls snap together?
Snap to Grid.

Quick Rotate?
I completely fucking forgot where it is...
But ill tell you later xD

I have snap to grid on, but I must be doing something wrong, because things pretty much do whatever they want, and don't seem to snap. Now that I think of it, though, maybe my grid is just set to be way too small...

Use "[" and "]" to change the size of your grid. A good number is 16, especially when you begin a new map.

Like train said use that setting for easier placement.  If you use one of the higher settings you can "snap" the brushes next to each other much easier.  If you're having a hard time doing that make sure you zoom in on the grid w/ the mouse wheel, the farther out you are the harder it is to get them next to each other; basically you want to have the grid lines as zoomed in as they'll allow that way you're working w/ one entire gridline (I know that probably doesn't make much sense, but hopefully you'll get an idea.)

As for rotation press ctrl + m and use that menu to rotate about the z axis, put the degree you wanna rotate and you're good to go.

Awesome, thanks guys! I'm enjoying learning how to map, hopefully I stick with it long enough to actually be able to make an actual map...I put together a "working" map last night that had a spawn room with a team-specific door and everything and a control point. It looks terrible, but I was proud that it actually worked. Heh.

Congrats.
Good luck.
If you ever need help, feel free to chat me up.
Username is da10x...

and all of the map making community, Cames99 here