Acrylic nails are artificial extensions placed on natural nails using acrylic powder and liquid monomer. They are more durable and resistant to breaking than natural nails. The main advantages of acrylic nails are that they protect natural nails, can be shaped and decorated, and are very durable lasting 2-3 weeks. However, disadvantages include potential infections if not applied correctly, damage to natural nails during removal, bad smells from chemicals, and inhibited nail growth with prolonged use. Proper application and removal by a professional can help avoid health risks.