If you're planning on tinkering around with electronics, whether it's on a Raspberry Pi, Arduino, or anything else, you'll need to know at least a little bit of programming. Hackster.io sent out a survey to figure out which three languages people thought were the best to learn.
As for the hardware itself, Arduino led the pack, with the Raspberry Pi and Particle following behind. Obviously which language you learn and which platform you use is dependent on the project itself, but if you're not sure where exactly to start, C and C++ seem like a good place. Head over to Hackerster.io for the full results of their survey.
The Largest Maker Survey Is Here [Hackster.io]