Polymer flooding is an enhanced oil recovery technique that involves injecting a polymer solution into oil reservoirs. The polymer increases the viscosity of the water, helping it to move more efficiently through the reservoir and displace more oil. This method is particularly useful in reservoirs where traditional water flooding is less effective. By improving the flow of water, polymer flooding can help extract additional oil that would otherwise remain trapped in the rock formations. This technique is often used in conjunction with other methods to maximize oil recovery and improve the overall efficiency of oil production operations.