Artbeat 2016 from 6 to 10 p.m. Friday and 11 a.m. to 6 p.m. Saturday. Free, with a $3 suggested donation.

Somerville’s signature arts festival returns with dance troupes and more than a dozen bands, 75 craft vendors, food and all-age activities. The events starts Friday night with music and interactive performances; Saturday sees Davis Square shut down for craft vendors, music stages, dance in the Somerville Theater and more works along the year’s theme of “roots.” Information and a schedule is here.

Boston Poetry Marathon 2016 (with a party) from 7 to 9 p.m. Friday at Lilypad, 1353 Cambridge St., Inman Square, where donations are taken at the door, with a 9 p.m. Friday to 1 a.m. Saturday party that costs $10; and from noon to 11 p.m. Saturday and 1 to 5 p.m. Sunday at Outpost 186, 186.5 Hampshire St., Inman Square, where donations are requested.

The list of poets signed up to read at this event goes on and on and on, but it’s a fast-moving, eclectic event – each poet gets only eight minutes on stage. A schedule and other information is here. The opening night party features music by Thalia Zedek; Willie Loco Alexander; Mr. Hip; Christopher Barnes; Cuffs; and Weather Weapon. (And of course there’s a poetry component to the party, with some verse by Boston poet laureate Danielle Legros Georges, Jon Papas and Michael Peters.) Information about the party is here.

Berlioz’s “Symphonie Fantastique” by the MIT Summer Philharmonic Orchestra at 8 p.m. Friday at the Massachusetts Institute of Technology’s Kresge Auditorium, 48 Massachusetts Ave. Free.

This is about as emo as symphonic music gets. Hector Berlioz made this epic work for the biggest of orchestras all about himself as a lovesick teen growing in the early 1800s, pining away for unattainable loves. “Berlioz suffered from isolation and bouts of uncontrollable mood swings. These dramas, coupled with his fantasies of love and loss, provided Berlioz with the raw materials for his life’s work,” PBS says of the piece. Now it’s been chosen as the free concert for the 20th season of the Massachusetts Institute of Technology’s Summer Philharmonic Orchestra, made up of musicians throughout the area and institute community and directed by conducted by George Ogata. Information is here.

Breakdancing competition with DJ’ing from noon to 8 p.m. Saturday at Brooklyn Boulders Somerville, 12 Tyler St., near Union Square, Somerville. Admission is $10.

Prepare to see some amazing breakdancing, as this is a serious competition: There’s $650 in cash awaiting the winner in the bboy/bgirl category and $350 for the best poppers. Music will be provided by Bmilk, Dj ReezOne and Djirvstyle, with the potential for some freestyling as well. Information is here.

Rappers vs. Poets Contest from 8 p.m. Sunday to 1 a.m. Monday (with doors at 7:30 p.m.) at The Lizard Lounge, 1667 Massachusetts Ave., between Harvard and Porter squares. Admission is $7.

What, more poetry? Indeed – this is the second annual Rappers vs. Poets Contest, with eight masters of the spoken word on each team facing off to determine who will be the year’s Lizard Lounge champion. Hosted by Harlym 1two5, the event will see poets Art Collins; Jeannie Nunes; Joseph Skoot Mosby; Lexi Wight; Crystal Beck (also known as Navah the Butterfly); Wallace Coar Live; Michael W. Bonds; and Michelle La Poetica going up against rappers Marlon Carey (also known as Inphynit); Rexy Fortyfive; Sadi Diazabakana; Professor Lyrical; Estee Nack; Johnny Silva; Illin’ P; and Relentless The Tangible. Information is here.