Mexican Slang

What do “esse” and “seso” mean? I know they probably mean “dude” in general but is there a literal translation? These words are the subjects of salutations, as in, “yo esse”.

Ese literaly means “That (One)”.

Seso means “Brain”.

Fiends of mine that are hispanic and use these terms use them in this sense–“That One” in reference to an amigo is high praise, like “That one [is one cool dude]”.