Is arbitrum and arbitrum nova the same?

I'm curious to understand if Arbitrum and Arbitrum Nova are essentially the same thing, or if they differ in some significant way. As someone who's interested in the world of cryptocurrency and blockchain technology, I've come across both of these terms and am seeking clarity on their relationship. Can you help me distinguish between the two, and if they're not the same, explain the key differences between them? I'd appreciate your insights on this matter.