Why should we distinguish between text file and binary files when transmitting them? Why there are some channels designed only for textual data? At the bottom level, they ar
Important to add to the answers already provided is that text files and binary files both represent bytes but text files differ from binary files in that the bytes are understood to represent characters. The mapping of bytes to characters is done consistently over the file using a certain code page or Unicode. When using 7 or 8-bit code pages you can spin the dial when reading these files and interpret them with an English alphabet, a German alphabet, Russian alphabet, or others. This spinning the dial doesn't affect the bytes, it does affect which characters are chosen to correspond to the bytes.
As others have stated, there is also the issue of the encoding of line break separators which is unique to text files and which may differ from platform to platform. The "line break" is not a letter in our alphabet or a symbol you can write, so other rules apply to it.
With binary files there is no implicit convention on character encoding or on the definition of a "line".