Kevin MacLeod is "a guy who writes music for film." He says: "I just do it as much as I can. If I don't have a film to work on, I'll invent something that needs a soundtrack."

Search his name on YouTube and there are over 36K results. That's because MacLeod is a popular source of royalty-free music, which he provides for free under a Creative Commons license; all he asks in return is credit in the video's description. What this means is that you can go to his Web site, Incompetech, browse tracks by mood or genre, and then download the one that best suits your video. The FAQ on his site tells you all you need to know about using his recordings.

MacLeod doesn't know exactly how many YouTube users download his work every day, but it is a lot. "I remember one day I scanned through the top 20 featured videos and my music was in 11 of them," he recalls.

"Scheming Weasel," "Deliberate Thought," "Plucky Daisy" and "Sapphire Isle" are the most popular of his tracks among YouTube users (he's not sure why), but his own favorite is "Ghost Dance." "I did this as an opening theme for a Sherlock Holmes audio production, and I think it is perfectly fitting for the genre," he reveals. "The piano arpeggio technique is interesting, and fits well with the opening phrases, which are later picked up by the orchestra."

If you're a musician and you'd like to allow your work to be used for free under the Creative Commons, MacLeod has these bits of advice:

• Start by getting your own web site. There are a pile of aggregation sites out there who promise to add value to your works by setting them with hundreds of other composers, making it a one-stop shop for producers who need music. Using a site like that is a fantastic way to get lost in a sea of not-so-good music.
• Set up your site to be easy for people who are making films to find what they want. Make life easy for other people, and they'll appreciate it.
• Share your music as liberally as you can. I recommend the Creative Commons: By Attribution license. If you add stipulations like "Share Alike" and "Non-commercial," you're limiting the usage of your music. The goal is for more people to hear you, not less.
• Promote yourself. Hey, you have a free product; it isn't that hard of a sell!
• Be patient.
• And of course, Keep Writing Music (but if you're the kind who writes music, it isn't really possible to not write music).

Of all the videos that include his compositions, which are MacLeod's favorites? He's got a few, which he breaks down by type:

Narrative: "Balls of Mystery" by captainstargood



Non-Narrative: "51 things i found around my house" by HurricaneAubrey



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