Linear regulators are electronic devices that provide a stable output voltage from a varying input voltage. They work by dissipating excess voltage as heat, ensuring that the output remains constant even if the input fluctuates. This makes them ideal for applications where precise voltage is crucial, such as in powering sensitive electronics. These regulators are simple in design and easy to use, often requiring only a few external components. However, they are less efficient than other types, like switching regulators, especially when there is a large difference between input and output voltages. This inefficiency can lead to increased heat generation, necessitating proper thermal management.