A mnemonic is something used to help remember something. Verses and lists are commonly used.
To remember the difference between stationary (stopped) and stationery (paper, pens and other office consumables), children are taught that the office supplies word has e for envelope. Once heard, this makes it easy to remember the difference between the spellings. This is a mnemonic. 'Richard of York gave battle in vain' is used as an acrostic to help remember the colours of the rainbow- red (Richard), orange (of), yellow (York), green (gave), blue (battle), indigo (in), violet (vain).
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