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No. The book contains patterns of letters but their context is different than what you (the "English Language Application") can process.

Text Files

A computer application (a program) is the context for the bit patterns of the input and output files it uses. Without a context, the bit patterns are just abstract patterns.

Although there are some standard contexts (such as for text files), many applications use a context that is their own. For example, a new image format would be a new context and would require programs written to process data in that format.

If you could somehow inspect the surface of a disk and see the bit patterns stored in a particular file, you would not know what they represented without additional knowledge.

Often people talk of "text files" and "MS Word files" and "executable files" as if these were completely different things. But these are just sloppy, shorthand phrases.

For example, when someone says "text file" they really mean:

Text File: A file containing a sequence of bytes. Each byte holds a bit pattern which represents a printable character or one of several control characters (using a character encoding scheme such as ASCII). Not all control characters are allowed. The file can be used with a text editor and can be sent to a hardware device that expects ASCII character codes.

Files containing bytes that encode printable characters according to the ASCII convention have about half of the possible patterns. Software that expects text files can work with the ASCII patterns, but often can't deal with the other patterns.


A file compressor is a program that inputs a file and outputs a smaller file that uses bit patterns more efficiently that in the original file. A decompressor restores the compressed file to the original version.

(Thought Question: ) When an ASCII file is compressed, does the resulting file contain ASCII characters?

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