A verbal conjugation comprises the set of endings added to any verb in a language to distinguish the grammatical categories of Person, Number, and Gender. In Russian, Gender is indicated only by the Past Tense conjugations. In the Present Tense, however, each verb must bear one of six verbal endings indicating whether the subject of the verb is singular or plural, and whether it is the speaker (1st Person), the listener (2nd Person) or some object not participating in the conversation.
The English language has lost all but one of its Present Tense conjugation endings, the -s of 3rd Person Singular:
Singular Plural 1st Person I work we work 2nd Person you work yall work 3rd Person he work-s they work
Russian, however, like most other European languages, maintains a separate suffix for each of these forms.
Singular Plural 1st Person я работа-ю мы работа-ем 2nd Person ты работа-ешь вы работа-ете 3rd Person он работа-ет они работа-ют
The set of suffixes for a given stem is referred to as that stem's 'conjugation'. Russian has two such sets, Conjugation I (first conjugation) and Conjugation II (second conjugation).