1 Associations. 2  Associations between actors and use cases are indicated in use case diagrams by solid lines. 3  An association exists whenever an actor is involved with an interaction described by a use case.
Benefits of Volunteering. Volunteering supports the Exploratorium and promotes hands-on science, artistic expression, and educational innovation. Volunteers contribute to the community while gaining additional experience and new skills. They get to know each other at gatherings and special events and by sharing their ideas and experiences via an e-mail list.
Volunteering is generally considered an altruistic activity where an individual or group provides services for no financial gain to benefit another person, group or organization. Volunteering is also renowned for skill development and is often intended to promote goodness or to improve human quality of life.