It is common practice to have two separate information fields for a name - one for the first and one for the last name. If, once these data are collected, you want to treat the full name as one combined piece of information, you could use format like in the example above which returns a name like "Bruce Wayne".
Example: For an E-Mail
The format operator is also very useful if you want to insert collected information into a larger string, e.g. an email. Let's say you would like to inform a client called "Clark Kent" about three new messages, then you could use the format operator like this: