On Snapchat, you have the option to change your display name, unlike your username. Your username is set permanently on Snapchat so you can't change it. But if for some reason you don't like your display name, Snapchat lets you make changes.
Can you change snapchat username and display name?
When you add someone on Snapchat, your screen name is what they see and it allows them to identify your account.
Since you first created Snapchat, you've probably changed your name several times because as humans we sometimes like to update things that we no longer think represent things.
If you've had a peak at your friend's phone and have seen your display name when you Snapchat them, you may have noticed that your Snapchat display name on their phone is different from the display name you've changed it to.