BR meaning in General ?

Battle rap (also known as rap battling) is a type of rapping that includes bragging, insults and boasting content. Battling can occur on recorded albums, though rap battles are often recited or freestyled spontaneously in live battles, "where MCs will perform on the same stage to see who has the better verses".

Although never a battler, battle rap was loosely described by Diplomat's group member 40 Cal in the book How to Rap (2009) as "extracurricular" and he compares it to the dunk contest in the NBA. Battle rap has since developed into highly organized league events drawing in millions of dollars and views. Battle rap events themselves are usually "sold out". Mainstream artists such as Diddy, Busta Rhymes, Drake, Joe Budden, and Cassidy often attend or participate in battles to help increase its popularity. Rap battles are often written solely for the purpose of impressing people with technically inventive rapping, and knowing a wide variety of rapping styles and a wide range of MCs is recommended. Some MCs started out writing mostly battle raps and battling other MCs before they began making records.