OM, the lines are blurred for sure. Contemporary art is just that, art from the current generation without a true defended movement, thus devoid of a common philosophy.
Movements are well defined. Some last for only a short period like Impressionism ( thank goodness) and other movements are more major and long lasting, including serious influence on future art. Movements have a common philosophy.
Clear as mud?
The Modern & Contemporary has become a too easy and lazy catchphrase that is just not accurate.