Simple Changes and Significant Changes are differentiated by the type of correction required for the last name on a ticket. In cases of Simple Changes, minor typos in the last name, such as a slight misspelling, can be easily corrected at the time of request without the need for additional documentation. For example, changing "Kumaar" to "Kumar" would fall under a Simple Change. On the other hand, Significant Changes involve more substantial modifications to the last name, such as changing the entire surname from one name to another, like from "Swift" to "Alwyn". In such instances, passengers are typically required to provide official documentation, such as a marriage or divorce decree, to validate the change. This policy ensures that changes that are more significant and require legal verification are properly authenticated before being processed.