What causes boils on humans?

Boils, or furuncles, are usually caused by bacterial infections, primarily by Staphylococcus aureus. They occur when bacteria enter hair follicles or skin through small cuts or abrasions, leading to inflammation and pus formation. Factors such as poor hygiene, friction, and certain medical conditions like Diabetes can increase susceptibility to boils. Additionally, compromised immune systems may also contribute to their development.