The Salt requisite system is used to create relationships between states; the idea being that when one state is dependent on another, interdependency can be easily defined.

More detailed information can be found in related links.

The spelling REQUISITE (necessary) is correct.

Studying and working hard in class is requisite for having good grades.
Eating five servings of fruit and vegetables is requisite if you want good health.
These are the requisite books for social studies.

requisite: necessary

The word requisite means a thing that is necessary for the achievement of a specific end. Some synonyms for requisite are; essential, must, requirement, needful or indispensable.

The prefix for requisite is "re-," meaning "again" or "back." The suffix for requisite is "-ite," which is used to form adjectives denoting a particular quality or characteristic.