What is the difference between A-10 Warthog and A-10 Thunderbolt?

Could you please elaborate on the distinction between the A-10 Warthog and the A-10 Thunderbolt? I'm curious to know if there are any notable differences in their design, capabilities, or roles within the military. Additionally, are there any historical or operational factors that contributed to the naming of these two aircraft? Understanding these nuances would greatly enhance my appreciation for their unique contributions to the field of aviation.