As one of the fastest growing engineering disciplines, electrical engineering covers a wide range of tasks, from the development of plug-in hybrid cars to wind and solar power generation. An electrical engineer could maintain the wiring system in his office, but he could also fix the space shuttle’s wiring.

Here are five of the most interesting subdisciplines in electrical engineering:

Signal processing. An electrical engineer specializing in signal processing analyzes any digital or analog signal. You could develop speech recognition software or design the screen for a new digital camera.

Mechatronic. Well, this is technically not a subdiscipline of electrical engineering, but rather a combination of several disciplines. It combines mechanical and electrical engineering with computer programming and software design, and is responsible for creating complex systems. Mechatronics experts built the Mars rovers; they also designed the anti-lock brakes on your car.

Instrument engineering. An electrical engineer who works on measuring devices such as thermometers, flow meters, and scales is an instrumentation engineer. These tools are often a single component in a larger system, so instrumentation engineers must be well-versed in a variety of engineering disciplines.

Telecommunications. All communication signals must go from one place to another, regardless of the medium. And whether those signals go through fiber optic cables, satellites, or cell towers, a telecommunications engineer is in charge of maintaining those media.

Microelectronics. Electrical engineers working in this field develop, maintain, and manufacture capacitors, diodes, resistors, transistors, and other small components. Microelectronics engineers must be trained in semiconductor technology as well as materials science and chemistry.