Fossil is a distributed version control system.
Git is an open-source distributed version control system (DVCS)
"From the article it sounds like fossil isn t a database any more than git is a database"
from question "Is SQL the ''assembler'' of the NoSQL database world?"
"Fossil is another one that s easy to use i would say easier than git to learn but it uses an sqlite file to store your code and i m not sure if it scales to really big projects"
from question "Personal version control system to recommend"