Definition of a contrail: A contrail occurs when a plane travels at a high altitude (about 30,000 ft. or more) and compresses the air into a water vapor or ice crystals through jet engines or the wing tips pushing through the air. This trail disappears after a minute or so due to evaporation, because it's water.

Definition of a chemtrail: The term "chemtrail" is a relatively new word, which appeared in the last few years along with the appearance of chemtrails.
A chemtrail is very different from a contrail. At first a chemtrail might look a bit like a contrail. However, instead of disappearing like a contrail does, a chemtrail just keeps spreading out and forming a hazy cloud bank. These trails traverse the whole sky and stay for up to around five or even eight hours. They have been known to turn what was originally a clear blue sky into a grey haze.

Something is going on here. Open your eyes people. This can`t be good for us, in any way.