The expression "3 * 4" represents a multiplication operation where the number 3 is multiplied by the number 4. In this case, it means that 3 is added together 4 times. This can be visualized as having 4 groups, each containing 3 items. When you calculate "3 * 4," the result is 12. This means that if you have 4 sets of 3 objects, you will have a total of 12 objects. Multiplication is a fundamental arithmetic operation used in various fields, including mathematics, science, and everyday life.