The letter M in braille
dots 1-3-413 of 26⠍
M in braille is dots 1-3-4. M is C plus dot 3.
A capital M has the capital sign, dot 6, in the cell before it: ⠠⠍.
In Grade 2 (contracted) braille, m standing alone as a word means “more”.
Don't mix it up
Now write it yourself
Tap the dots for M, then Enter. On a keyboard, press F D S / J K L together and let go.
Remember it, don't just look it up
M is in Letters K–T. Braille a Day brings it back tomorrow to answer from memory, then again just before you'd forget. Five minutes a day.