I'm a non-electrical engineering student however want to gain knowledge and experience with different electrical programming systems. I'm confused however as to all the different components and their differences. For example, why/when would you choose a PLC over an Arduino board or do these two even compare? I'm primarily interested in things that will help in the construction of robots, automation tools, etc. so like how certain sensors work, circuitboards, etc. Any help is greatly appreciated, thanks!