There are many components that can be used in electronic and radio circuits. For each type there are variants and these may enable them to be used in different ways.
Learn about electronics online with our tutorials about passive components: resistors, capacitors, inducators, crystals and many more.
Active devices: transistor, FET, Vacuum tube / valve, thyristor . .
Batteries of all sorts are used in all forms of electrical and electronic equipment. From children's toys to smartphones, laptops and gadgets right up to electric vehicles.