Enhanced Oil Recovery (EOR) is a set of techniques used to extract additional oil from reservoirs after primary and secondary recovery methods have been exhausted. These methods can include injecting substances like water, steam, or chemicals into the reservoir to increase pressure and improve oil flow. EOR can significantly boost the amount of oil that can be recovered from a well, often increasing production by 5% to 15% or more. Common EOR techniques include thermal recovery, gas injection, and chemical flooding, each tailored to specific reservoir conditions and oil types.