Stress and Strain
This really great video explains it as well: https://www.youtube.com/watch?v=aQf6Q8t1FQE&ab_channel=TheEfficientEngineer
Stress is a quantity that describes the distribution of internal forces within a body.
The deformation of an object in response to stress is characterized by a quantity called strain.
Relationship between stress and strain
where is Young’s Modulus