This block follows the history and evolution of video codecs, showing how each generation improved compression efficiency, quality, and technical capabilities. Readers learn how the industry moved from MPEG-2 to H.264/AVC, then to H.265/HEVC, VP9, AV1, VVC, and AV2 — and why some codecs became widely adopted while others remained niche. The block explains both the technical and practical sides of codec evolution: better prediction, larger coding blocks, more advanced transforms, improved entropy coding, higher bit depths, HDR support, hardware acceleration, browser and device support, licensing issues, and patent complexity. By the end, readers will be able to compare codecs not only by compression efficiency, but also by ecosystem maturity and real-world usability.