Final answer:
Brittle materials are those that will fracture or fail as they are stressed past their design limits. They do not undergo plastic deformation and instead break suddenly. Examples of brittle materials include glass and ceramics.
Step-by-step explanation:
Materials that will fracture or fail as they are deformed or stressed past their design limits are considered brittle. When stress is gradually increased beyond the elastic limit, brittle materials such as glass or ceramic will undergo brittle fracture. Unlike ductile materials like metals, brittle materials do not exhibit plastic deformation and instead break suddenly.