Informal learning is learning-on-the-job, or any learning not systematized—such as mentoring and coaching. Like its ancestor in the Middle Ages—the apprenticeship—informal learning is a vital part in any training and learning program, particularly when deployed in conjunction with formal training and performance classes. Informal learning can include a wide array of activities ranging from brown bag lunches and collective learning sessions to virtual learning communities on the Web.
Victoria Marsick and M. Volpe (eds.): Advances in Developing Human Resources: Informal Learning On the Job.