However; Decimal; Hex - AMSTRAD cpc 6128 User Instruction

The next level of shorthand for binary is the kilobyte (kByte or simply 'K') which is
1024 bytes. 1024 is the nearest binary multiple to the more familiar decimal use of
the term 'kilo' (1000) - and explains why a computer described as having a '64K'
memory does in fact have a memory of65,536 bytes (64 x 1024).
Thankfully, the BASIC interpreter does all the necessary conversions for you, and it
is quite possible to become a proficient programmer without a complete
understanding of binary, although an appreciation of the significance of binary will
help you spot the many 'magic' or significant numbers that inevitably crop up as you
work through the science of computing.
It's worth spending some effort to acquire an understanding of binary and the various
significant numbers 255, 1024 etc, since it is very unlikely that these will change
from being the bedrock of computer operation in the foreseeable future. The certainty
and simplicity that comes from working in only two states will prevail over the
enormously increased complexity that would result from any other number base.
However ....
Simple and elegant as it is, binary notation is longwinded and prone to inaccuracy as
it cannot be easily read at a glance. Binary has a number of associated counting
systems that act as shorthand for programmers. One such number system widely
used in micro computing is called HEX (an abbreviation of hexadecimal).
Here the number is based on 16 (0 to 15), and is represented in a single character:
Decimal
o
1 2 3 ·4 5 6 7 8 9 10 11 12 13 14 15
Hex
0 1 2 3 4 5 6 7 8 9 A BC DE F
The hexadecimal system can break the eight bits of a byte into two blocks offour bits,
since 15 is a four bit number: 1111 binary. The first block indicates the number of
complete units of'15', and the second indicates the 'remainder' - and this is where the
absolute elegance of binary and hex begin to emerge.
At your leisure ....
Chapter 9 Page 11