Affective factors are emotional factors which influence learning. They can have a negative or positive effect. Negative affective factors are called affective filters and are an important idea in theories about second language acquisition.
A learner's attitude to English, to the teacher, to other learners in the group and to herself are all affective factors and have impact on how well she learns.
In the classroom
Affective factors may be as important for successful language learning, if not more so, than ability to learn. Teachers can reduce negative factors and develop positive ones by doing activities to build a positive group dynamic, by including students in deciding aspects of the course and choosing activities that are motivating for the age and interests of the learners.