I've seen how Ubuntu is based on Debian, and how Manjaro is based on ArchLinux.
What is Elementary OS based from?
May I also ask on how the bases differentiate the OS itself?
Yes. The most easily available resource to find out such things is a site called Wikipedia, accessible with a web browser. There you can find an article on Elementary OS that answers both of your questions:
Elementary OS (styled "elementary OS") is a Linux distribution based on Ubuntu.
The Elementary OS project aims to solve a number of perceived deficiencies in the established desktop environments, namely:
- better global aesthetics by streamlining the user interface;
- reduce software dependency by using core applications written in the C language or Vala;
- diminish the need to access the terminal.