Whoooo, this could be a very long and complicated question to answer. Do you want the very basic components names ? Or a run down of each part and their function ?
You see, many here have a vast variety of knowledge, and this question for those who really understand the subject would be a subject one could spend literally days to explain. Sometimes the more you know the more difficult it becomes to answer a question. There are simply so many vectors the conversation could take.
I looked for a link to provide, but am not pleased with what was offered by searching " Basic Rifle Components " . With the variety of firearms these days, the technologies has move far beyond just a basic rifle. What used to be the basic components have now evolved into many part with much different names and functions.
So from the top of MY mind I would simply answer this way :
A rifle in it's basic components is :
1) A receiver
2) A barrel
3) A bolt ( or breech block ) contains the firing pin also
4) An trigger mechanism
5) An action ( the method of ejecting shells, and reloading )
6) sights
7) a stock
I would say " basically " that covers it. I believe that the basic components listed provide a better basic explanation then I was able to find in a quick search. You could certainly search each individual component now to find more.