Not quite.
1. I write a long story and assign random numbers to each symbol.
2. I give you the sum of the numbers.
3. When I send you a file, an equivalent sum guarantees it is original.
It is a verification method to ensure file integrity when it’s released. Anyone can compare the hash to ensure their file is not corrupt.
The first cypher I ever used was “a sunflower.” A=0, S=1 through R=9. In any given document, you would count the occurrence of each letter, multiply by the value and add them up for the hash code.
Can’t recall what I coded it in. Might have been C shell.