What is always in front of you but cannot be seen?

Published , last checked . Re-solved cold against the published wording before it went live: how puzzles and answers are checked.

A one-line riddle for a quick win. From the free puzzle set on Think Fanny. Next try Two coins add up to 30 cents.

Think Fanny riddle graphic with a bold question mark

The puzzle

Warm up with a one-liner before the harder logic set.

What is always in front of you but cannot be seen?