Generic conventions of music videos.

The main conventions of a music video would be the editing part of cutting fast, the cuts would be no longer than 10 seconds.
Some other extra conventions would be something like dancing, however not in all videos. There are other conventions such as performance which there are dancing as mentione before, singing and sometimes artists who play instruments then occationally
you see them with an instrument. Also the costumes would differ according to the genre. For example in R&B/Rap music videos the costumes worn would be baggy clothes, jeans and heavy jewellery. However in Rock music videos the costumes would be like skiny jeans and leather jackets e.c.t... They also would probably be holding an instrument like an electrical guitar.

Two Genres of music. Pop and R&B

Pop music is an abbreviation of 'popular'. It is a commercially recorded music, and often orientaited towards a youth market. It's usually short and simple love songs. Examples of popular artists from pop music would be groups such as ABBA and artists such as lady gaga and Justin bieber etc... I think the group ABBA is popular because they construct their music in a way that they use different types of music to blend in with pop, such as techno, indie, etc... I think artists like Lady gaga is popular is because she sort of creates her music in a wacky way. However the king of pop is Micheal Jackson, who is a legend in pop.
R&B is an abbreviation of Rhythm and Blues. It is a genre of popular African American music. Examples of Popular artists from the R&B genre would be Rihanna and Usher etc...