Blindness and visual impairment refer to a range of conditions that affect a person's ability to see. This can include complete blindness, where no light perception is present, or partial vision loss, where individuals may have limited sight. Causes can vary widely, including genetic factors, eye diseases like cataracts or glaucoma, and injuries. People with visual impairments often use various tools and techniques to navigate their environment. These may include braille for reading, canes for mobility, and assistive technology like screen readers. Support services and rehabilitation programs are also available to help individuals adapt and maintain independence.