Torque is the tendency of force to rotate something around an axis. Torque helps you turn a doorknob, it makes a car's tires spin, it basically helps a force act in a circle.
Applications of torque equations can help solve real world problems.
Locations for supports for bridges can be determined by examining the effects of the torque vehicles would cause on a bridge. An engineer looking to efficiently maximize the potential for producing torque in an engine would choose electrical or diesel power over gasoline power to use the fuel effectively.
People who would like to easily compare weights without a scale can easily use torque properties to their advantage, specifically with a balance. Putting a weight at each end of a beam and sliding it over a fulcrum until it balances can help determine relative weights of objects by comparing the lengths of sides of the balance.
For example, Person A and Person B are on opposite ends of a log, and the log is balanced. The leg extending to Person A is twice as long as the one extending to Person B. because torque is the length of the arm multiplied by the weight of the object, it can be determined that, because the torques balance, Person B has twice the weight of Person A.