There are many programming languages to learn. For SEO, the programming language you choose depends on what you plan to do with that language and how you plan to implement changes from that language.
Ruby is an incredibly easy language to learn, and there's a lot of evidence why it is simple to break into and start.
New research finds that a natural aptitude for learning languages is a stronger predictor of learning to program than basic math knowledge. Want to learn to code? Put down the math book. Practice ...