What does the shield next to my name mean?

[Reaptor]

I notice other people's names have different shields. What does that mean and how do I change it?

[ImHelping]

They change along with your title you can select, which you get more options for every 5(?) levels. That and super citizen from the deluxe pack.

[Joe da Immortal]

The Shield is your rank Insignia to correspond with the Title selected.