Any verb using "have" or "has" as its auxiliary verb is in the present perfect tense.
Any verb using "had" as its auxiliary verb is in the past perfect tense.
The same can be said for the verb "to have" --
She has had two sandwiches for lunch each day this week.
They have had this television service for two years.
If he had had a sandwich for lunch, he wouldn't be hungry now.
http://www.englishpage.com/verbpage/presentperfect.html = present perfect
http://www.englishpage.com/verbpage/pastperfect.html = past perfect
Check out the other tenses in the list at the left.
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