What did john calvin mean by "predestination?

What he meant by "predestination " is, God ordains salvation for certain people at birth. According to John Calvin, predestination is God’s unchangeable decree from before the creation of the world that he would freely save some people (the elect), foreordaining them to eternal life, while the others (the reprobate) would be "barred from access to" salvation and sentenced to "eternal death.