You can’t expect to learn about robots if you don’t hack or play with them. The HR-OS1 Humanoid Endoskeleton is a powerful robot designed for educators and researchers. It is a humanoid platform that you can build yourself. It has an onboard Linux computer and can be customized with 3D printed parts. The HR-OS1 is a hackable, modular, and humanoid robot.
The robot has 20 AX-12A robot actuators. It comes with an Arbotix-Pro robocontroller. It has a Raspberry Pi 2 CPU with a SD card. WiFi and Bluetooth dongles are available too. More information is available here.