The Sampling Theorem states that a continuous signal can be completely represented by its samples if it is sampled at a rate greater than twice its highest frequency. This critical rate is known as the Nyquist rate. For example, if a signal has a maximum frequency of 1 kHz, it should be sampled at least at 2 kHz to accurately capture all its information without losing any details. When signals are sampled correctly, they can be reconstructed perfectly from these samples. This principle is essential in various fields, including digital audio, telecommunications, and signal processing, ensuring that we can convert analog signals into digital formats without losing quality.