A good answer might be:

Efficiency

Most digital data is stored in binary files. Pure text files are somewhat rare (probably less than 2% of the data in the world). There are several reasons why binary files are used.

I. Input and output are much faster using binary data. Converting an integer to characters takes time. Not a great deal of time, but some files (such as image data) consist of millions of numbers. With that many numbers the accummulated conversion time is significant.

II. A binary file is usually very much smaller than a text file that contains an equivalent amount of data. For image, video, and audio data this is critically important. Small files not only save storage space, but can be transmitted faster and processed faster. IO with smaller files is faster, too, since there are few bytes to move (see above).

III. Some kinds of data can't easily be represented as characters. For example, the bytecodes of a Java class file or the machine language of an executable file. You may not usually think of this as data, but of course, it is. The Java compiler reads an input file (a source file) and writes a binary data file containing its results (the bytecode file).

QUESTION 6:

Large text files can be compressed with a utility program like PKZip. Often a compressed file is less than half the size of the original.

Can the compressed file be read with a FileReader stream?