These terms refer to two similar activities that are commonly used to practice the use of English in the classroom. Both activities are generally popular with students and teachers alike, as they can be both entertaining and productive when carried out correctly. During a role play activity each student is allocated a specific part and/or personality to play within a particular scenario such as a visit to the doctors, a workplace meeting or a family get together, these activities are often improvised and can be quite unpredictable. During a simulation activity the students recreate situations that they might find in the real world such as ordering a meal in a restaurant or buying a bus ticket, these activities are generally more structured in their design than role plays.
Both these activities are useful ways to practice a variety of language skills, as well as for encouraging interaction within the student group. They also give the students confidence in using English within the safety of the classroom before they have to use it in the real world.