To see the documentation on a standard C function, such as fopen(…), fgetc(…),
feof(…), or fclose(…):

In Vim (normal mode):  Put cursor over the function name and type shift-k.

In bash, type (without the '$'):

  $  man feof
  $  man fgetc

To search the man page:   /feof«ENTER»

To exit the man page viewer:  q
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A byte contains 8 bits.
Each bit has 2 possibilities:  0 or 1
A byte has 256 possibilities:  00000000 to 11111111 (binary)
                                   0x00 to 0xFF     (hexadecimal)
                                      0 to 255      (decimal)
A byte can be represented by TWO hex digits (e.g., 0x8F).  <<<<<<<<<<<<<<<<<

A nibble contains 4 bits and can be represented by ONE hex digit.
Nibbles aren't very useful.

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