javascript because 1) you can program anywhere, 2) it has incredible libraries for multimedia and interaction which makes it fun, 3) you can share the results

javascript because 1) you can program anywhere, 2) it has incredible libraries for multimedia and interaction which makes it fun, 3) you can share the results with one click to anyone 4) it is a highly marketable skill a lot of other people are recommending python which is fine if you are into the command line and file IO. if you prefer the web, then JS is the way to go.