Critical. A vulnerability whose exploitation could allow code execution without user interaction. These scenarios include self-propagating malware (e.g. network worms), or unavoidable common use scenarios where code execution occurs without warnings or prompts. This could mean browsing to a web page or opening email.
A strain is a stretching or tearing of muscle or tendon. A tendon is a fibrous cord of tissue that connects muscles to bones. Strains often occur in the lower back and in the hamstring muscle in the back of your thigh. Initial treatment for both sprains and strains includes rest, ice, compression and elevation.
Tensile, Compressive and Bending Stresses and Strains. Stress represents the action of a force or moment on a structural member. If the force pulls the member (tension) it results in a tensile stress; if the force pushes the member (compression) it results in compressive stress. Tensile stresses stretch a member and compressive stresses squeeze a member.