But before we get into transduction, let's recall what a bacteriophage is. A bacteriophage is a type of virus that only infects bacterial cells and it hijacks the machinery of the bacterial cells and it uses the cells to build its own viral genetic information. Now, sometimes these bacteriophages accidentally take up a fragment of DNA of that bacterial cell instead of using its own viral genetic information. Now, when these harmless bacteriophages infect other cells, other bacterial cells, they inject the cells, they inject into the cells the DNA fragment from the other cell which can then be integrated with that cell's DNA. And this increases the genetic information of that bacterial cell. So basically, in a way, transduction takes place accidentally.