This chapter presents two prominent and connected strands in research on puns. The first is the classification of different types according to taxonomies using a range of criteria. The second is the phonology of imperfect puns, where a punning word evokes a target that is slightly different in sound than the pun itself. The chapter discusses the taxonomies of different types of puns and the phonology of imperfect puns, some general theoretical observations need to be made. From a very broad viewpoint, most humorous texts can actually be considered to contain a pun. The chapter deals with two related issues that are more important in their linguistic rather than their humorologistic importance. First, taxonomies of puns are discussed, much in the vein of and based on Attardo's section, Taxonomies that operated with linguistic, rather than humorological criteria, use factors mainly from phonology and rhetoric. Puns that are homographic but not homophonic are called eye puns.