Unauthorized transactions refer to any financial or payment-related activity that has not been approved, sanctioned or initiated by an individual or entity with proper authority. This can include fraudulent activities such as credit card fraud, identity theft, and other forms of cybercrime where a person's account or personal information is used without their knowledge or consent to make purchases or conduct transactions. Unauthorized transactions may also refer to any financial activity that goes against an individual’s pre-set spending limits or exceeds their credit limit, if applicable. In such cases, the affected individual may be held responsible for repaying the debt and may face legal consequences depending on the severity of the situation.