Green and yellow: grounding wires. They don't transport energy but usually divert it in the event of an electrical failure, preventing possible electrocutions.
Blue: the neutral wire that, in the past, was identified with the color red. In some countries, such as the United States, this function is also assigned to white cables.
Brown, black, or grey: phase cable par excellence; it is responsible for transmitting the electric current.
Colors with stripes: these serve as a guide since these are neutral, such as blue or white, which help identify which neutral wire goes with a different colored one.
Other colors: used for current or charging functions. The most common is red, and they are usually used in installations where there are many cables so that they can be easy to identify and then differentiate their use.