Musical genre. Involves cutting and pasting samples and loops from two or more popular tracks to form a new track, often forming a suprisingly catchy new tune. Not as complex as remixed music. There are a number of bedroom djs who create moderate quality mashups.
The more different the genres of the source tunes, the more effective the mashup.
You downloaded the Run DMC vs Tom Petty mashup? DJBC is an artist, man.
An aspiring DJ who is still at the "hobby" stage, who creates/destroys/modifies music on home computers and whatever equipment they can afford, often from their bedroom. While bedroom dj's may not be particularily skilled, they make up for this with enthusiasm and creativity.
Many great bootleg remixes and mashups available on the web are care of these artists.
- you downloaded that remix of Basement Jaxx by DJ SS? That dude's a genius!
- DJ Sharpie Sharp? He's just a bedroom DJ, bro, he's still at school.