American Sign Language(ASL) is a predominant sign language among hearing-challenged communties in North America. It is also claimed as the third most widely used language there.
At Indiana University, four-leveled American Sign Language(ASL) courses are offered by the Department of Speech, Language and Hearing Science(SPHS) under the COAS.
"You can take the ASL sequence to fulfill your College of Arts and Sciences foreign language requirement and the General Education World Language requirement."(from SPHS website)
Informal ASL learning opportunities:
American Sign Language (ASL) is a complete, natural language that has the same linguistic properties as spoken languages, with grammar that differs from English. ASL is expressed by movements of the hands and face. It is the primary language of many North Americans who are deaf and hard of hearing, and is used by many hearing people as well.
Quote from National Instituition of Deafness and Other Communication Disorders（NIDCD）.
The boy's gesture in the picture means"I love you"(Photo Credit: NIDCD)