One

Following the previous topic, today's theme is one.

One has similar specification with zero; multiplied or dividend with one, the number doesn't change.

In Roman numeral, one is expressed with the character 'I'. 'I' descends not from the letter 'I' but from a notch scored across the stick.

As a trivial episode, many older typewriters do not have a separate symbol for '1' and use the lowercase 'l' instead.

And because of this, it is possible to find cases when the uppercase 'J' is used instead, while it may be for decorative purposes.