Cramps, also known as spasms, are involuntary contractions of muscles that can cause pain and discomfort. They often occur in the legs, but can affect any muscle in the body. Common triggers include dehydration, overexertion, or prolonged sitting or standing. These muscle contractions can last from a few seconds to several minutes. While most cramps are harmless and resolve on their own, persistent or severe cramps may indicate an underlying health issue. Staying hydrated and stretching regularly can help prevent cramps from occurring.