This particular debate is a never ending one and there is no concrete answer to what is the exact difference. Do not read further if you are expecting this to be a binary discussion. I will try and justify to the best of my ability what the difference is. We can start by stating that Hip-Hop is a culture and rap is a genre. Hip-Hop is often used for describing RnB music. One major aspect of this argument also revolves around the type of culture that each type of music personifies.
Hip hop culture can be traced back to the late ’70s. The production was so organic that that they used beat-box style of music. Later, this was exemplified by groups like Sugarhill Gang and Fab 5 Freddy. Initially, their intention was to rap in upbeat tempos which instructed people to get off their seats. Rap, on the other hand, is now concerned with what is going on in the community. Lot of times a few tracks are also pop in nature.
The rap starts of the late 90’s and 2000 brought drug dealings in it. Artists like Eminem, 50 Cent, and Lil’ Wayne used to rap about where they are from, their views on political issues.
Origin and Objectives
Since the origin of hip hop, it’s main objective was to push listeners towards a better tomorrow. On the other hand, Rap music has more of a reporting function of “Telling it like the way it is”. It can be perceived as something more crude when compared to other elements. The first all star rap group, N.W.A, is often repudiated because of their hardcore lyrics but for them, that was the only way to survive.
If you compare that with a song like “Rapper’s Delight” by The Sugarhill Gang, you would be comparing apples and oranges. The song encouraged people to have a good time with their lives and stimulated them to think only about the better things.
In a way if you look at a lot of (not all) rap music, it tends to have a more ominous or sombre outlook at situations when compared to hip hop. Everyone who follows the culture uses the two terms interchangeably, to the extent that it becomes difficult to interpret what the actual difference is. As mentioned above, it is next to impossible to get a pinpoint answer to what the difference is, it is our perception about the both that will forever continue the debate.