The term used to describe the introduction of foreign DNA into a host cell is transfection. This process is utilized in genetic engineering and research to introduce new genetic material, allowing scientists to study gene functions or develop genetically modified organisms. Different methods, such as electroporation, lipofection, and viral vectors, are employed depending on the type of cells being targeted. Successful transfection can lead to the expression of new traits or proteins in the host organism, facilitating advancements in biotechnology and medicine.