What does MKV x264 - YIFY mean?

x264is a free software library for encoding video streams into the H.264/MPEG-4 AVC format. MkV stands for matroshka format, a russian format often used for encoding files. MKV format provides good video quality with subtitles embeded in a small video size.however the sound may be somewhat compromised, nonetheless its quite a popular format. YIFY is a signature used by the uploader.