The following is quoted from the "Venturer Handbook":

Venturing is the young adult program of the Boy Scouts of America for men and women 14 (who have completed the eighth grade) through 20 years of age. Local community organizations such as professional organizations, churches, and civic groups initiate specific Venturing crews. They do this by matching the interests of young adults with the people and program resources within their own organizations.

For example, a local scuba diving shop could start a Venturing crew and invite young adults interested in high-adventure activities to join. A church might have adults that could provide leadership and program support to a Venturing crew that does service-oriented projects like building Habitat for Humanity houses or working at day-care centers and retirement homes. A Boy Scout troop could organize its own crew for young men and women to enjoy high-adventure activities and to train younger Cub Scouts and Boy Scouts.

The program of the Boy Scouts of America is to provide young adults, through these community organizations, an effective Venturing program designed to build character, promote citizenship, and develop personal and mental fitness. Each crew has the responsibility of achieving this purpose by designing its own program. (End Quote)

For scouters who are just learning about venturing, here's some main differences in the program:

The age difference (See above)

Although there are awards to work toward, there are no ranks

There is a national recommended uniform (the green shirt), but the uniform is set by the individual crews

It is more youth run

Venture Crews can do more high adventure than scout troops, such as white water rafting.