Relays are typically categorized based on their operating principles, and each type offers distinct advantages and applications. The most common types include electromagnetic relays (EMR), solid-state relays (SSR), and thermal relays.

    Electromagnetic Relays (EMR): This is the traditional relay type, which operates through an electromagnetic coil. When the coil is energized, it creates a magnetic field that attracts a movable armature, closing or opening the circuit. EMRs are widely used because of their simplicity, reliability, and cost-effectiveness. However, they can have slower response times and are susceptible to wear and tear over time due to mechanical parts.