Mapping Question (SIMPLE)

Do I need to add lights to maps when I make them if it is an outdoor map?

Well, that’s quite simple, but no replies?
If you’re plan is to create a map with only light from the environment, then yes.
Use the the entity light_environment. Without any lights, your map will appear fullbright, which isn’t nice at all. Good luck!

im really dumb…what program do you use to Build a map?..

Hammer Editor in the SourceSDK.