Cognitive behavioural therapy (CBT) was developed by Aaron Beck in the 1960s to treat depression. It is based on the theory that thoughts, feelings, and behaviors interact and influence each other. CBT uses cognitive and behavioral techniques to help patients identify and change distorted or unhelpful thoughts and behaviors. Some techniques include cognitive restructuring, exposure therapy, and behavioural experiments. CBT has been shown to be effective for treating various mental health issues like anxiety, depression, eating disorders, and substance abuse.