This refers to the video compression standard. H.264 is the most common format for HD video, offering high compatibility with smartphones, smart TVs, and computers.
In the world of digital releases, the first version to hit the internet isn't always perfect. If an uploader realizes there is a stutter in the video or that the Hindi audio track is slightly delayed, they release a "Patched" version. For the viewer, downloading a patched file ensures a seamless experience without the technical glitches found in the initial "v1" release. Visual Quality vs. File Size
This indicates the content source—likely a TV series (S03 referring to Season 3).