Normally, the two eyes point in the same direction. A "squint" or "strabismus" occurs when the two eyes are misaligned. This can happen in either eye and the misalignment can be in any direction.A squint may occur for a number of reasons. 

Some-times, one or more of the muscles that move the eyes is in the wrong place. Sometimes the muscles do not work as they should. A longstanding squint does not usually affect vision, although the squinting eye may be "lazy".

A recent squint can result in double vision and should be fully investigated.