The five basic doctrines of Calvinism are represented by the acronym T-U-L-I-P. These doctrines are:
T = Total Hereditary Depravity. At birth all men are depraved wholly and totally. They are in this sinful condition because they have inherited it from their parents.
U = Unconditional Election. God, before the foundation of the world, arbitrarily chose to save some people and destroy others and nothing can be done to change God's sovereign decree.
L = Limited Atonement. Christ died only for the ones God had unconditionally chosen to save.
I = Irresistible Grace. An unregenerate person cannot voluntarily believe in God but once God determines to save him, that same individual cannot overcome or resist the power of God no matter what he may desire.
P = Perseverance of the Saints. Since man can do nothing but evil on his own, God's unconditional election is required to save him. Consequently, one needs to do nothing to remain saved. If one's salvation depended on himself in any way, the miraculous work of God in saving him would be overthrown.