For the most part, a *flare* refers to a sudden release of light and energy that doesn't leave the vicinity of the Sun. The material that travels through space is called a Coronal Mass Ejection (CME for short) and they can reach all the way out past Earth. Flares and CMEs are related but not the same thing. They often occur together though, which can get confusing.
http://youtu.be/bydoOMytcZM