Arduino is the de facto starting place for new hobbyists. It's a very low barrier to entry and runs on pretty much anything. If you want to learn networking at

Arduino is the de facto starting place for new hobbyists. It's a very low barrier to entry and runs on pretty much anything. If you want to learn networking at an Internet of Things level, look at the Spark Photon (basically an ARM dev board with a TI CC3000 WiFi module). It's only $19. The documentation is fantastic, hence I would recommend it over say the ESP2866 which is super cheap but a bit more... hacky.