Most combat ships install either an Integrated Targeting Unit (ITU) or a Dedicated Targeting Core (DTC), with the exception of more specialized variants.
OP cost: 4/8/15/25
ITU completely supersedes the inferior DTC, except that Integrated Targeting Unit can be hard to aquire. DTC exists as a backup for ships that absolutely require the range bonus, such as some cruiser & capital ship builds.
Only up to date for version 0.8a-RC19. It is likely still broadly correct but not verified for the most up to date data yet. Please double check the Version History