Intelligence (or Intel), in the Space Empires series refers to the use of spies and saboteurs to gain information about your enemies (or your friends) and then carry out covert attacks behind the lines of conflict.
Intelligence during se4 race setup
Confusingly, the term intelligence is also used in Space Empires IV during game setup. Players can spend racial points on "intelligence" in order to improve their research aptitude. Just to muddy the waters further, players can improve their aptitude for intel by spending points on "cunning".