Hey Jules! This is the condensed version from Wikipedia. 
Busking is when artists (musicians, clowns, street artists, etc.) perform live in public places to entertain people.
People busk for a variety of reasons, including for money, for fun, the attention they get, to socialize or meet people, the love of their art, or to practice their skills or try out new material in front of an audience. Some buskers only work part time, while others make a full time living performing on the streets. Some buskers do professional entertainment gigs in addition to working the streets.
Some people manage only pocket change from busking, while others can amass substantial incomes. An act that might make money at one place and time may not work at all in another setting. A busker's income depends on many conditions, including the composition of the audience, the type and quality of the performance, the weather, and the time of day. Location can be the key, and competition from other entertainers can also play a role, both positively and negatively.
Busking can be the bottom rung of the entertainment industry, and some of the most famous groups and superstars started their careers as buskers. Examples include the Cirque Du Soleil, Stomp, Bob Hope, George Burns, Rod Stewart, Dolly Parton, Eric Clapton, Simon and Garfunkel, Jimmy Buffett, Bob Dylan, Joan Baez, Judy Collins, Pierce Brosnan, Robin Williams, Jason Alexander, Beck, and Joni Mitchell.