This document discusses various tests and classifications for eye alignment. There are four main types of alignment tests: cover tests, corneal reflex tests, dissimilar image tests, and dissimilar target tests. The cover test is the most commonly used test and can accurately measure deviations. Eye alignment is also assessed in secondary positions including near fixation, cardinal positions, and midline positions. Abnormalities in secondary positions may indicate conditions like convergence insufficiency. Classification of eye alignment includes categories like orthophoria, heterophoria, and heterotropia as well as patterns like A or V patterns.