Musical touchstones come in two variations: There are the ones that people remember (Motown, Thriller, Rebecca Black) and there are the ones people don’t remember that they remember. An example of the latter is Flood, the third album by long-running nerd-rock institution They Might Be Giants.

Ask yourself: Do I know the tune to “Particle Man”? If you attended middle school between the years 1989 and 1993, the melody may have appeared from out of nowhere in your brain just now. Sing it with me: “Particle Man, Particle Man / Doing the things a particle can / What’s he like? / It’s not important / Particle Man.”

Good luck thinking of anything else for the next 72 hours. (Sorry.)

Flood turns 25 this week, and it’s been about that long since I listened to it on a semiregular basis at my friend Adam’s house in the seventh grade. The guys in my peer group discovered R.E.M. and Monty Python at around the same time, and Flood proved to be a perfect transition between our Green and The Final Rip Off tapes. Flood wasn’t exactly funny, and it wasn’t exactly pop music — it was a fun-house reflection of alt rock and a more melodic (and less vulgar) iteration of the smart-ass shtick we were endlessly mimicking after school. One half of They Might Be Giants, John Flansburgh, chuckled when I told him this during an hour-long phone conversation last month.

“I mean, you know, 15 years earlier John Linnell and I were listening to Firesign Theatre albums and Frank Zappa records, and it wasn’t that different,” he said.

Equal parts goofy, earnest, odd, and square, Flood was such a constant presence in those years that I didn’t have to purchase my own copy to fully integrate it into my consciousness. When I revisited the album recently, I found that I was shockingly conversant with the deep cuts beyond Flood’s signature songs, “Birdhouse in Your Soul” and “Istanbul (Not Constantinople).” There’s the Beatles-esque piano ballad “Dead,” which is the one about dying and coming back as a bag of groceries. There’s the hooky “Someone Keeps Moving My Chair,” which is the one about how someone keeps moving your chair. There’s “Twisting,” which is the one that sounds like ’60s oldies radio and advises that girls aren’t to be trusted because they may set your goldfish free. There’s “Minimum Wage,” which is the one about working for the man, because every indie-ish album released in the early ’90s had to have at least one song about working for the man.

What’s remarkable about Flood in retrospect is that a major label, Elektra, decided that a weird-ass duo from New York’s Lower East Side who gleefully mashed up polka, punk, prog, and pop should be considered part of mainstream culture. And, somehow, that’s precisely what Flood became. The album went platinum, it spawned a slew of successful MTV hits, and it briefly made Linnell and Flansburgh legitimate, recognizable rock stars.

“I’ll tell you one thing that really blew my mind: Remember the Columbia Record [Club]?” Flansburgh, 54, inquired. Actually, I do. I’m almost positive my buddy Adam procured his copy of Flood via the mail-order service, which was well known among middle-schoolers at the time as the most effective way to steal music.

“I remember seeing Flood as one of the records you could get for, like, a penny,” Flansburgh said. “Which was actually a real premium place to be, [because] there was only a finite number of records you could pick that were on the sheet of 50 albums or something. [I remember] thinking, Wow, we are really in the mainstream. To be one of the records in the Columbia House Record Club, it’s the real stuff. I felt like we were in the Carpenters.”

As Flansburgh himself had remarked with a knowing laugh moments earlier, “It’s funny how completely different the culture is now from then. In terms of just the issues and the politics and sort of the culture of music-making, there’s just so many elements to what was happening then that [have] no relevance now. It’s like talking about, you know, dinosaurs.”

But Flansburgh doesn’t think of himself as a dinosaur. On the contrary, he believes that They Might Be Giants can still be as big as ever, and he’s prepared to work very hard this year to make his aspirations a reality. 2015 is shaping up to be perhaps the busiest year in TMBG history — on top of a monthly residency this winter at Brooklyn’s Music Hall of Williamsburg and a national tour in spring, They Might Be Giants plans to release a new song per week for the next 12 months, or 52 songs in all. (The latest track, “Erase,” went up this morning.) Flansburgh and Linnell have also revived their Dial-A-Song service — launched originally in 1983 from Flansburgh’s Brooklyn apartment — which allows fans to call a toll-free number (844-387-6962) to hear the duo’s latest music.

“The idea is to find new audiences, and we’re ambitious about that, which probably seems crazy. I mean, we’ve been in this band for 30 years; a lot of people would just be like, We are exactly as big as we’ll ever be and that’s what it’s gonna be,” he said. “I think a lot of what we’re doing is kind of hard to explain, but I don’t think it’s hard to understand. I think we come out of an American culture that is much more universal than it might appear. People have said to us, you know, we don’t remind them of musicians but we do kind of remind them of their cousin.”

At first I laughed when Flansburgh said that. But then I realized that he was being serious and also that he was absolutely correct. He does remind me of my cousin.

Speaking with Flansburgh is a lot like listening to his music — the tone is witty, playful, and self-deprecating, but the sentiments expressed are almost always sincere and sneakily grandiose. If Flood penetrating the pop audience seems extraordinary a quarter-century later, what’s even more incredible is that They Might Be Giants is still around and striving to push beyond its niche.

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Pals since grade school, Flansburgh and Linnell were shaped musically by attending punk and new-wave shows in the late ’70s. Flansburgh was enough of a regular at CBGB to recall the excellence of the sound system nearly four decades later. (“Any band would seem like a very powerful outfit playing through that,” he insisted.) Around the same time, on a solo trip to London in 1977, Flansburgh saw one of Elvis Costello’s earliest gigs. When asked whether seeing a guy wearing Buddy Holly glasses onstage planted a seed, the bespectacled Flansburgh said he was struck more as a 17-year-old by the 21-year-old Costello’s wedding ring. (“It just made me think, This guy is way more of an adult than I even understand.”)

Flansburgh and Linnell’s songwriting style was apparent early on: For the most part, they eschewed conventional, first-person narratives, instead favoring a more literary approach that allowed them to take on the perspectives of made-up characters, from ersatz superheroes to reincarnated produce.

“I think, like so many things, your strengths and your weaknesses can be really closely related,” Flansburgh said. “We were very shy about writing regular love songs just for the reasons that any regular person would be. It’s just a little bit embarrassing. It can often seem kind of sexist and just too personal. For us, songwriting is a very dynamic kind of fiction writing. We experiment a lot with unreliable narrators and different points of view and sort of extreme ideas. There’s sort of a fantastical aspect to a lot of our songs.”

He submitted an upcoming Dial-A-Song track, “Madam, I Challenge You to a Duel,” as an example. “The entire conceit of the song is that it’s about an extremely formal person, like the kind of person that would challenge someone to a duel — only that the twist is that they are challenging a lady to a duel, which breaks every code of behavior in the world of dueling,” he said, adding with a chuckle, “This is not based on a personal experience of mine.”

Back in the ’80s, Dial-A-Song was both an outlet for Flansburgh and Linnell to showcase new tunes — no matter how zany, raw, or half-baked — and an appropriately unconventional venue that spotlighted the performance-art aspect of They Might Be Giants. They advertised via personal ad in The Village Voice and culled the songs from a suitcase full of tapes set up next to the answering machine. Each day, they would put in a different tape.

“It doesn’t seem like a very off-the-wall idea now, just living in the electronic world that we live in, but I do remember at the time people not really understanding what it could even be,” Flansburgh said. “I’d grown up in Boston, where there was this thing called Dial-A-Prayer, [which was basically for] the elderly.”

Flansburgh and Linnell kept Dial-A-Song going for years after they became a major-label act, finally opting to disconnect it in 2006. Now, Dial-A-Song is so retro that it just might be TMBG’s future. Flansburgh expects to release the band’s latest songs on an album (or series of albums) at some point, but for now the piecemeal approach seems like “an appropriate response to the way the world is now,” he said. “It used to be you put out an album and it would be like, This is your new album for this year. And then it was like, Here’s a new album for this month. I’ve noticed the last couple of album cycles, a week after the album is out, it just seems like it’s already old news.”

The Dial-A-Song project is not unlike the promotional rollout utilized by the king of nerd rock, “Weird Al” Yankovic, for his chart-topping 2014 release Mandatory Fun, except even more demanding. Whereas Yankovic cannily released eight music videos over as many days to exploit the unquenchable appetite of nostalgia-prone Internet aggregators, garnering reams of free publicity in the process, They Might Be Giants hopes to attract the public’s interest with fresh, irresistibly catchy, and easy-to-post content for a whole year.

It seems safe to assume that They Might Be Giants’s loyal fan base will turn out this year no matter what the band does. From virtually the beginning of the group’s touring and recording career — Flansburgh and Linnell started They Might Be Giants in 1982, and early on gigged around New York as a duo backed only by a drum machine — the people who liked them really liked them, even as the rest of the world was flummoxed.

“Howard Thompson, the man that signed us to Elektra Records in 1989, saw us perform to a packed house in 1985 and had no interest in signing us,” Flansburgh said. “There was just nothing to talk about. When we actually created a small body of work with successful, unusual rock videos on MTV, and the world of college radio and alternative rock had kind of metastasized throughout the United States, it suddenly seemed like it wasn’t just about some downtown New York bunch of weirdos.”

After the alternative boom went bust and MTV moved on, Flansburgh and Linnell ferreted out fans and financial opportunities in unexpected places. They wrote the theme song to Malcolm in the Middle, performed the theme to The Daily Show With Jon Stewart, and contributed 20 songs to a Dunkin’ Donuts ad campaign. In 2002, the group got a boost when it recorded a children’s album, No!, based on the concept of kids wanting music that’s purely entertaining and “not packaged in its redeeming qualities,” Flansburgh said.

Ironically, the album was so successful that TMBG was later contracted by Disney to do a series of children’s records and DVDs that did have overt educational value. “It’s a pretty straightforward challenge as a writer, you know,” Flansburgh said. “Writing about letters is like a pretty fat assignment.”

While No! proved to be a gateway for a new generation of listeners, Flood remains the most common introduction to They Might Be Giants. Flood even inspired an entry in the 33⅓ book series on landmark albums in rock history. The volume on Flood, written by no fewer than two PhDs, credits They Might Be Giants with “giving a new social, technological, and ultimately economic legitimacy to what we might call geek culture.”

“I guess we would embrace that kind of idea if it didn’t make it seem like an inside joke or something,” Flansburgh said of TMBG’s cult status. “I think the thing that works against cult-y bands in general is there’s no room for newcomers. For us, we work very hard at keeping the invitation open to the general public. We definitely have recidivists. I’m not saying there isn’t a cultlike quality to our audience, but the truth is, most of the people in the crowd discovered us somewhere along the 30-odd years that we’ve been playing. They weren’t at the Pyramid Club — nobody who saw us at the Pyramid Club is coming to our shows anymore.”

Just as Flood washed up in countless Middle American bedrooms and spoke to a generation of smart, awkward teenagers 25 years ago, Flansburgh hopes They Might Be Giants can percolate in pop culture again — unexpectedly, perhaps, but indelibly nonetheless. Then again, “going mainstream” may be another one of those elements that mattered once in the ’90s but is now irrelevant. After all, what is pop culture now but a series of niches curated by proudly self-identifying nerds and serviced by desperate corporations hoping that the Comic-Con faithful turn out for the latest $200 million superhero movie? Perhaps They Might Be Giants truly is part of a culture that is more universal than it appears. In which case, they are giants.