LDPC (Low-Density Parity-Check) codes are a type of error-correcting code that allows for efficient data transmission over noisy communication channels by using a sparse bipartite graph to represent the parity-check matrix. They offer near Shannon-limit performance and are widely used in modern communication systems, such as 5G, Wi-Fi, and satellite communications, due to their excellent error correction capabilities and iterative decoding algorithms like belief propagation.