I wouldn't expect you to memorize this for an exam. It is important to know such mechanisms of action, to understand how can we eventually destroy microorganisms. Each lytic bacteriophage has a mechanism for packing its genome into a proteinaceous capsid. Some phages occasionally package fragments of host DNA instead. This occurs randomly with respect to the host sequences that are packaged, and therefore any bacterial gene can be transferred.
Generalized transduction allows the transfer of virtually any bacterial gene.
In other words, any bacterial gene stands an equal chance of being transduced to a recipient cell. The process of specialized transduction depends on the lysogenic state of the bacteriophage genome. A bacteriophage genome is excised from the bacterial chromosome by a special recombination mechanism that results in precise excision of the phage genome. This mechanism, however, is not perfect and sometimes excision occurs in such a way that a nearby gene is included in the excised DNA, and this leads to specialized transduction of that gene. Most lysogenic bacteriophages genomes integrate at particular locations, called attachment sites, in the bacterial chromosome.