Both verbs are in the infinitive form. You are right, говорить is imperfective and поговорить is perfective. The conjugations are as follows: Past Imperfective говорил (masculine singular) говорила (feminine singular) говорило (neutral singular) говорили (plural all genders) This can roughly be translated as "have been speaking", "were/was speaking", "spoke". Perfective поговорил (masculine singular) погоыорила (feminine singular) поговорило (neutral singular) поговорили (plural all genders) This can roughly be translated as "have spoken", "spoke". Present Я говорю Ты говоришь Он говорит Мы говорим Вы говорите Они говогят This can mean "I (you, he, she, it...) speak, am speaking" The perfective form, since it is perfective, when it is conjugated... it automatically is conceived as future. It has the same endings, as the imperfective version in the present, but it does not convey a present meaning, but a future one. Future Я поговорю Ты поговоришь Он поговорит Мы поговорим Вы поговорите Они поговогят This can be translated as "will speak", "will have spoken". The impefective future is: Я буду говорить Ты будешь говорить Он будет говорить Мы будем говорить Вы будете говорить Они будут говогить This can be translated as "will speak" or "will be speaking.

поговорить is more to talk while говорить is to speak. поговорить is for the 'perfect' tense and also used as an infinitive but говорить is infinitive as well. There are some different cases how and when to use this forms. I'd be glad to explain it to you if you wish.

Ok! Thank you everyone!

Given my level of russian I shouldn't really be answering questions about russian! However, I think it is with noting what Dimitriy says here. The "по" prefix often makes a verb perfective with the meaning to do something for a while. Combine this with Mario's explanation below and I think you have a fuller understanding of the distinction.

поговорить (о чём-либо, с кем-то) - to talk (about something, to someone) It's more like 'To do some talk'. Same as 'to do some thinking'. I got some thinking to do. 'Мне нужно подумать'. It indicates the fact that you have to do it FOR A WHILE. A short, or a long one, depending on how long it takes.