'It's easy to remember things that rhyme, so #C00, #B00,...'

From the comments on 'Hexadecimal Colour Mnemonics'

Chris wrote:

It's easy to remember things that rhyme, so #C00, #B00, #D00 and #F00 are all various shades of red.

Bearing in mind that the hex system describes colours in the order Red, Green and Blue (RGB) it is then easy to swap the red rhymes round thus: #00F, #00B, #00C etc to give different shades of blue. And the same with shades of green. Substituting numbers 1-6 for the letters gives you even more shades of the basic colours. Not quite a mnemonic in the strictest sense, but still helpful.

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