How can cells be transformed?

Cell transformation refers to a genetic change of cells. Cell can be transformed when it takes in foreign DNA from its surrounding environment and expresses the genes encoded on that DNA, acquiring new characteristics as a result. Natural transformation is a common phenomenon in bacterial cells. It can also be achieved artificially in a laboratory by using certain chemicals, applying heat shock treatment, or electroporation. 

For transformation to be successful, the recipient cell must be competent, which means it should have the ability to be altered easily. Laboratory techniques aim to artificially induce competence in the host cell.