Simple past: -ed ending: "I finished the project"
Present perfect: have + -ed ending "I have finished the project".
The perfect emphasizes that the action is completed; the present perfect is used when the state that results from its completion extends into the present (contrast with the past perfect "I had finished the project", where the reference point for the resultant state is in the past).
The simple past merely emphasizes that the event took place in the past.
(Thanks to Fruz at Dictionary.com)
http://forums.delphiforums.com/dicti...es?msg=14104.1
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