It's called the "present perfect" because it includes the word "have" which is the present tense of the verb "have".
I finish. (Present tense)
I finished. (Simple past)
I have finished. (Present perfect)
I had finished. (Past perfect)
I am finishing. (Present continuous)
I was finishing. (Simple past continuous)
I have been finishing. (Present perfect continuous)
I had been finishing. (Past perfect continuous)
Note that in the continuous, there would be something after the relevant form of "finish".
Both the simple past and the present perfect are used to describe an event which happened in the past and which is now over. We use the simple past usually with a time marker and the present perfect when the time period is unspecified or unimportant.
I lived in Madrid from February 2009 until August 2010.
I have lived in Madrid.
I ate an apple for breakfast.
I have eaten an apple.
I bought bread yesterday.
I have bought bread.
However, sometimes the present perfect is used with something which looks like a time marker. For example, "I have bought bread at the same shop for ten years". The present perfect is used there to indicate that you still buy bread at the same store you have bought it at for the last ten years. If you no longer buy bread there, you would say "I bought bread at the same store for ten years but then I realised that the artisan bakery round the corner sells much better bread so now I buy it there".