Look at below for definiton of conditional sentences:
Conditional sentences are sentences expressing factual impilcations or hypothetical situations adn their consequences. They are so called because the validity of the mail clause of the sentences is conditional on the existance of certain cumstances, which may be expressed in a dependent clause or may be understood from the context.
Condition deal with imagined situations : some are possible, some are unlikely, some are impossible. The sepaker/writer imagines that something can or not happen or have happened, and then compares that situation with possible consequences outcomes,...