Community is a difficult word to define. In a world where young people communicate transcontinentally and instantaneously via digital mediums like Twitter and Gchat, while their parents stay in at night with a few hundred channels of HD television, it sometimes seems hard to find examples of physical, functioning communities. That is, unless you count clicking “Like” on somebody’s Facebook post as genuine person-to-person interactionI, for one, do not.

In my mind, this remains the most special aspect of the Triangle music communitythat it is, in fact, a community. Collections of like-minded artists huddle together in their respective townsDurham, Raleigh, Chapel Hillinspiring each other to create. Far from separating themselves from the rest, these artists then mingle across geographic and genre lines, sharing ideas and sometimes members, pushing ideas forward with seemingly ceaseless momentum. It doesn’t always work perfectly, but it does create a rich and open artistic atmosphere.

If you’re reading this, then you don’t have to look far for proof: This year’s Hopscotch Music Festival is chock-full of local artists who are not just great on their own merits but have also played big roles in building the area’s music culture into the well-rounded community it is today.

Thursday night’s show at the Lincoln Theatre is a prime example. SPIDER BAGS, LAST YEAR’S MEN and THE LOVE LANGUAGEthree of the area’s most energetic and engaging rock bandsopen for Atlanta garage rock outfit Black Lips. It promises to be one of the most entertaining shows during this year’s festival, but it also displays a scintillating new talent playing alongside two of the bands that helped them along.

Last Year’s Men, formed about two years ago by Chapel Hill’s Ben Carr, is a tenacious, old-school garage band in the vein of the Reigning Sound. They inject youthful intensity into rock most often enjoyed lately by those in their 30s or 40s, taking sad-bastard jams on an amphetamine-fueled late-night joy ride. Early on, Dan McGee, who started Spider Bags the better part of a decade ago, took Carr under his wing, listening to his songs and giving him tips. He went on to produce the band’s debut LP, covering it in the same fuzz that makes the Bags’ tangled, writhing rave-ups so appealing. Carr’s writing has much in common with the brokenhearted salvos of The Love Language’s Stu McLamb, although McLamb favors big, ’60s-inspired pop-rock. McLamb picked up on the resemblance, scooped up LYM and gave them an opening slot at a show in Wilmington early this year. At that point, it was the Men’s biggest road date.

Now, though, Last Year’s Men are busy touring the East Coast and playing showcases for Scion A/V Garage. They could be next year’s next big thing, but you should take that proclamation with a disclaimer: I have worked for the record label that released their debut. (Indeed, connections around here run deep.)

More than simply sharing relationships, many local acts playing the fest share key members. HORSEBACK, the long-standing experimental metal and noise project of Chapel Hill’s Jenks Miller, plays the Berkeley Cafe on Saturday. These days, Miller’s live band tackles the A-side of his engrossing 2009 album, The Invisible Mountain, replicating its methodically ominous march with slow, sludgy riffs and Miller’s wildly creepy snarl. The patience Miller brings to his slow-building metal is also the secretly brilliant component of MOUNT MORIAH, the Southern-tinged rock band in which he plays guitar. Headlining the Berkeley on Friday, the band hinges on the modestly twanged croon of Heather McEntire, who explores painful tales of love and family. As McEntire pierces through with gorgeous heartache, Miller matches her with guitar lines that smolder. It’s a testament to the bond between McEntire and Miller, best friends who together co-own local imprint Holidays for Quince.

So, a metal mastermind serving as the spark for a folk-rock act? That might seem a strange pairing, but it’s far from the least likely local collaboration you’ll see at Hopscotch. SHIRLETTE & THE DYNAMITE BROTHERS, who play Hopscotch’s free The Rosebuds & Friends day party outside Lincoln Theatre on Saturday, pair the socially conscious Durham rapper and poet Shirlette Ammons with a lively Chapel Hill classic rock act named The Dynamite Brothers. Falling somewhere between psychedelic funk and ’70s AM rock, the Brothers create a lush backdrop that alters its emphasis between rhythm and melody, giving Ammons the opportunity to push from captivating, syncopated assaults to a smoothly sensual murmur. Their 2011 EP, And Lovers Like, also includes some ace local collaborators, who might just make an appearance on Saturday. Most notable is former Carolina Chocolate Drop JUSTIN ROBINSON, who appears at Hopscotch with his MARY ANNETTES Friday at The Hive at Busy Bee. Robinson teamed with the band to remake his song “Kissin’ and Cussin’,” twisting his macabre graveyard march into a scary though somehow sexy late-night hip-hop creep.

Shirlette and the Brothers obliterate boundaries, but that doesn’t set them apart here, either. Raleigh’s WHATEVER BRAINS, openers at Kings on Friday, cross-pollinate influences from the Triangle’s fertile hardcore and garage scenes, building a thoroughly entertaining brand of scuzz-punk you won’t hear anywhere else. Their velocity and rhythmic intensity favor hardcore, and it makes sense; three of them serve in the volatile Raleigh punk band Shards. The Brains hoard a bevy of other influences, deploying them with joyous and aggressive irreverence. Their “Gross Urge” uses hyper-effected new wave synths and processed drums in a punk-paced romp about a priest with a most unseemly itch. “The Future of Porn” runs headlong with a pretty typical rock ‘n’ roll shuffle before bursting through in double-time hardcore, accomplishing more in a minute and a half than most garage rockers can with an entire album. Straddling boundaries, Whatever Brains have become double-duty ambassadors, playing on both hardcore and garage bills. They draw those scenes closer together.

At Hopscotch, a host of other integral Triangle artists offer local entry points. The bittersweet indie jangles of Raleigh’s THE ROSEBUDS are gateway pop for local music newcomers, and their worldwide touring makes the duo key emissaries to the indie rock community at large. Durham duo THE FOREIGN EXCHANGE, who headline the Lincoln on Friday, are spokesmen for the area’s R&B and hip-hop communities, using their +FE Music imprint to promote local artists. Live, the Exchange strip the synths from their shimmering R&B, opting for bright acoustics, which highlight the warmth in ex-Little Brother Phonte Coleman’s voice. Perhaps no act has been more crucial to Triangle music than SUPERCHUNK. Formed in 1989, they gained notoriety for the area with their highly charged pop-punk jolts. Maybe more importantly, singer Mac McCaughan and bassist Laura Ballance founded Merge Records, now one of the world’s most successful independent labels. Superchunk plays City Plaza on Saturday.

With an established history and a healthy network of promising up-and-comers, the Triangle music scene is among the most bountiful in the country. Come Thursday, there will be a multitude of great bands vying for your attention, but it would be a mistake to miss all of the ones that play these clubs month in and month out. Without them, Hopscotch wouldn’t happen.