How to replace this recessed light bulb
Some types of compact fluorescent (PLL, PLT) have a push-in fitting. Try pulling straight out.


Photo by ikiwaner, Creative Commons Attribution-Share Alike 3.0 Unported



P.S. While you are working on that, you really ought to fix that loose earth/ground connection with a bolt, nut, washer and maybe a crimp-on ring-connector. Or something similar. —

P.P.S. broken compact fluorescents may need special cleanup