Bloggin' Background

I've been toying with the idea of a background image for the past few weeks, but could never quite get the code/image to match up right. The image you now see is my third or fourth foray into this coding experimentation, and although I sort of understand some of the code I've yet to understand why it finally worked this time but failed so miserably in my earlier attempts.

So now that there is a glimmer of comprehension I really don't loose these stupid things:

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEj_9YPnA99-5y2FMd3Vpn3zOhEIyizpLiluklQMspUirARdu5b_OULoweEfruSidW71gqsd2H5bBCJr-jsD8dyuQyE1CoKfEaDP28PtA3RpCPcqKNNdel4w-Xhbox8QfLJ9c-UXcw/s1600-r/scar-circlebw.jpg

https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEgg099QGGzdPcVbkzCc8Adl-q80dl6ZMVz_gGH6vZlFwK_OFqTxWq0Ovta6OPUcDEXly8deBryRpvanpLx13Dp47GTajTvMMi-q8Pivjad0YtHvFivCo93ThGn9DBPT3_Vv6mk_2Q/s1600-r/scar-circlebw2.jpg

Massive Bonus Points for image identification :)