imported post
What do you understand and what don't you? A complete run down of all gun laws will undoubtedly be rather lengthy. I certainly can't get into all of it (I'm still getting up to speed on CA gun laws) but I'll try to touch on a little bit of it.
No OC within 1000' of a school. Some exceptions for private property, but even the exceptions have exceptions, so personally I'd just try to avoid that altogether if at allpossible.
The weapon must be unloaded (this includes an empty magazine, or no magazine at all in the weapon). You may carry full magazines on your person, openly, or bullets not in a magazine in your pocket/concealed.
You may OC in a vehicle. Be very careful that it's not obstructed (concealed)by things like armrests. Same thing about proximity to schools applies, so there are potential problems if you drive near a school, regardless of if you know it or not.
Not a law, but carrying an audio recorder on your person while you're OC might be in your best interest should you get hassled, so you have proof of the events of the encounter. If there's a password or means of locking the device to prevent someone from turning it off or erasing the contents of the recording that could be useful (not sure if such a thing exists, here in Idaho the laws are so much nicer and hassle-free, so I don't bother).
I'm sure there's much more, and others will fill in where I missed or messed up (I think that's all correct though, verify anybody?). Hope it helps.