Set Addition is a mathematical operation that combines two or more sets to create a new set containing all unique elements from the original sets. For example, if you have Set A with elements 1, 2, 3 and Set B with elements 3, 4, 5, the result of the set addition would be 1, 2, 3, 4, 5. In set addition, duplicates are not counted more than once. This means that if the same element appears in multiple sets, it will only appear once in the resulting set. Set addition is a fundamental concept in set theory, which is a branch of mathematics focused on the study of sets and their properties.