quality:correction, information:classification
Case

Although English has largely lost its case system, personal pronouns still have three morphological cases that are simplified forms of the nominative, objective and genitive cases:

Most English personal pronouns have five forms: the nominative and oblique case forms, the possessive case, which has both a determiner form (such as my, our) and a distinct independent form (such as mine, ours) (with two exceptions: the third person singular masculine and the third person singular neuter it, which use the same form for both determiner and independent), and a distinct reflexive or intensive form (such as myself, ourselves). The interrogative personal pronoun who exhibits the greatest diversity of forms within the modern English pronoun system, having definite nominative, oblique, and genitive forms (who, whom, whose) and equivalently coordinating indefinite forms (whoever, whomever, and whosever).

Forms such as I, he, and we are used for the subject (" I kicked the ball"), whereas forms such as me, him and us are used for the object ("John kicked me ").