Here are some of the things you might see in the equipment you take apart.
Capacitors are nonconductors that are used to store electrical power.
They are used in circuits that are tuned to a particular frequency. Diodes are semiconducting crystals that allow electrical current to flow only in one direction. Each IC is made for a specific task and many are used in combination. LED's , or light-emitting diodes, produce light from electrical current, giving the kind of electronic display found on older calculators and digital watches. Since they use so much power, they have largely been replaced with liquid crystal displays in newer equipment.