Ad hoc sampling refers to the process of selecting a sample of data or individuals in an unplanned or impromptu manner, often in response to a specific research question or problem. This method allows for a quick and targeted collection of information, without the need for a pre-determined sampling plan. Ad hoc sampling is commonly used in situations where time and resources are limited, but a timely and relevant sample is needed for analysis. It is a flexible and dynamic approach that can yield valuable insights and inform decision-making in a variety of fields, including market research, social sciences, and data analysis.