The .TS file format is used to broadcast high-definition TV (HDTV) - it is specifically designed for less reliable transmission and broadcast fits well with this. When the signal gets degraded the transport stream (TS) can handle error correction and stream synchronization issues much better than other formats.
Transport stream (TS) is specified in MPEG-2, and it is a standard format for transmission and storage of audio, video, and data, and is used in broadcast systems such as DVB and ATSC. Various elements make up a transport stream - namely; Packet - A packet is the basic unit of data in a transport stream, PID - Each table or elementary stream in a transport stream is identified by a 13-bit packet ID (PID), Programs - Transport stream has a concept of programs. Each single program is described by a Program Map Table (PMT) which has a unique PID, Program Specific Information(PSI) - There are 4 PSI tables: Program Association (PAT), Program Map (PMT), Conditional Access (CAT), and Network Information (NIT), PAT - PAT stands for Program Association Table. It lists all programs available in the transport stream, PMT - Program Map Tables (PMTs) contain information about programs, PCR - To enable a decoder to present synchronized content, such as audio tracks matching the associated video, at least once each 100 ms a Program Clock Reference, or PCR is transmitted in the adaptation field of an MPEG-2 transport stream packet
MP3 is a digital music format which allows CD tracks to be reduced to around a tenth of their normal size without a significant loss of quality. MP3 gets rid of a lot of the information recorded in a song that our ears are not able to hear and then uses complex algorithms to reduce the file size. This then enables you to get hundreds of songs on to a CD and it also has opened up a new market over the internet - the download market as download times have been significantly reduced.
The MP3 format is a lossy format. That means that an MP3 file does not contain 100% of the original audio information. Instead, MP3 files use perceptual coding. In other words, that means it removes the information that your ear doesn't notice thereby making the file smaller. The reason lossy formats are used over RAW is that RAW audio files are too large to travel over the internet at any great speed. By using lossy formats it enables even dial up users to download mp3 files at a reasonable speed. RAW file formats generally require 176,000 bytes per second compared to a lossy format which requires 17,600. The difference is massive and so are the download times.