A fungal infection is an infection caused by the overgrowth or invasion of fungi, such as yeasts or molds. Common types of fungal infections include athlete's foot, ringworm, and candidiasis, which can affect the skin, nails, or mucous membranes. These infections may occur in healthy individuals but are more prevalent in those with weakened immune systems. Symptoms can vary widely, from mild irritation to severe, systemic infections. Effective management typically involves the use of antifungal medications and addressing contributing factors.