1. Basic:Something simple and not complicated, serving as a foundation for further development.
2. Elementary: A more formal term than "basic," often used to describe a fundamental level of knowledge or skills.
3. Fundamental:Describing something as both basic and important, often associated with principles, rights, changes, or problems.
4. Rudimentary:A formal word indicating a basic or undeveloped level of knowledge or simple and undeveloped body parts, equipment, or systems.
5. Essential:Relating to the most important qualities or elements of something or someone, forming the core foundation.
6. Underlying:Referring to something that serves as the basis or foundation upon which something else is built or established.
These words can be helpful when describing the starting point or foundational aspects of various subjects or concepts.