Antimicrobial agents are substances that are used to kill or inhibit the growth of microorganisms such as bacteria, viruses, fungi, and parasites. These agents are commonly used in medicine to treat and prevent infections in humans, animals, and plants. Antimicrobial agents can be classified into several categories, including antibiotics, antiviral drugs, antifungal medications, and antiparasitic drugs. They work by targeting specific mechanisms in the microorganisms, such as inhibiting cell wall synthesis or disrupting essential metabolic processes. Research in antimicrobial agents focuses on developing new compounds with improved effectiveness, reducing the development of resistance, and studying the mechanisms of action of existing agents.