Waves, in the context of signals, are disturbances that transfer energy through space or a medium. They can be classified into two main types: mechanical waves, which require a medium like air or water, and electromagnetic waves, which can travel through a vacuum. Common examples of waves include sound waves and light waves, both of which carry information. Signals are often represented as waves in various fields, such as telecommunications and audio engineering. In these applications, waves can encode information through variations in amplitude, frequency, or phase. This allows for the transmission of data over distances, enabling communication between devices and people.