Everyone knows the theme from "Rugrats" (we'll pause here while you hum a few bars of it), but not many people know the man who wrote it: Mark Mothersbaugh.

Mothersbaugh is a composer who has created more music for cartoons than he can remember, including "Rugrats," "Rocket Power" and "Clifford the Big Red Dog." He also has been involved with video games, movies and the rock band Devo, which toured with Tony Hawk's Boom Boom Huck Jam last fall.

Right now, he's working on music for "Rugrats Go Wild," a movie due out this summer. (Mark Mothersbaugh now does the music for "Rugrats" movies while his brother Bob does the TV show. Since Mark is older, we think that makes him Tommy to Bob's Dill.) Recently, he spoke with Michael Cotterman.

How did you get involved with "Rugrats?"

I wrote some music to listen to at home to fill the space. Something I could play in the house with no lyrics, like audio aromatherapy. My friend in Japan said he would put it out, so I put out this album called "Music for Insomniacs." A few years later I got a call from ["Rugrats" co-creator] Gabor Csupo. He said he liked "Music for Insomniacs" because it was "childish and simple." He told me about "Rugrats." I told him I've done a half-dozen kids' shows and he said, "Oh, I didn't know."

So I wrote the theme song and scored the pilot. That's how it started.

How does it work? Do you see each episode and then write music for it?

About 95 percent of the time, you're writing for a picture that's already put together.

How long does it take?

Usually about four or five days for a half-hour show.

In "Rugrats," does the music change for different characters?

Oh, yes. They all have different sounds. The woodwinds and orchestral instruments are for adults. For the kids, it's more toy piano and synth [synthesizer] sounds. More kind of playful and less sophisticated. My brother Bob's scores are a little different. Bob has scored the shows for the past four years, and I do the features [movies].

What makes cartoon music work? That it gets noticed or doesn't get noticed?

There is no written law there, because there are so many different versions of animation, so many styles and so many levels of sophistication.

How many cartoon theme songs have you written?

(Laughs.) I don't even know how many. I've written 45 theme songs for television shows. Over a third of that is for cartoons.

What was the first TV show you wrote music for?

"Pee-wee's Playhouse." I wrote the theme song and scored the first run of episodes, then every other.

What other cartoons use music well?

There's a lot that do. I always loved "Ren & Stimpy." "South Park" uses music well. So does "The Simpsons."

How old were you when you wrote your first song?

Probably like 14, and they were really bad, too. I remember writing songs down in the basement. I'd make up my own little songs. I was in a band, but they weren't interested in playing my songs.

How did the creative relationship with your brother Bob start?

He used to make 8mm films when he was in ninth grade. I was an unwitting participant in some of those. In high school, we were in a band he had called the Jitters. For a brief period of time I played organ in his band. Later on at Kent State I met Jerry Casale and started Devo. When we were looking for a band I brought in both my younger brothers, Bob and Jim. We couldn't get anyone else to play with us.

Any advice for kids interested in your line of work?

Pay attention to music and sound in everyday life. See if you can figure out what it is that makes you like it. Make yourself think about why you like it, so that someday you can think about how to do it yourself. It's a great line of work to get into.

When the Rugrats go wild in the movies, they're doing it to Mark Mothersbaugh's music.Mothersbaugh has written more than 45 TV theme songs.