Facebook's use of Instagram photos to train artificial intelligence raises privacy concerns.

The social media giant recently announced that it had built software that can learn from what it looks at. The program was taught to recognize images by looking at more than 1 billion public photos. Experts say users should be aware that Facebook is using their photos.

“It's all about knowing consent,” said James E. Lee, director of operations for the Identity Theft Resource Center, in an email interview.

“Instagram’s privacy policy, which most people probably don’t read, makes it very clear that the company reserves the right to use the photos you post for research. Users can turn facial recognition on or off in their privacy settings.”