Antibiotics are powerful medications used to treat infections caused by bacteria. They work by either killing bacteria or inhibiting their growth, allowing the body's immune system to fight off the infection. Common examples of antibiotics include penicillin, amoxicillin, and ciprofloxacin. They are not effective against viral infections, such as the common cold or flu. It is important to use antibiotics responsibly to prevent antibiotic resistance, a situation where bacteria evolve and become resistant to these medications. This can make infections harder to treat and can lead to longer hospital stays and increased healthcare costs. Always consult a healthcare professional before using antibiotics.