Ask HN: What is considered an AI Engineer?

I keep seeing a lot of job postings from companies looking for an AI Engineer, and I can't wrap my head around what exactly they're looking for.

Are they maybe looking to update their solutions or products to provide AI features that would make them more appealing? Incorporate AI into their processes to become more effective? Write their own models?

I guess my question really is, how do you prepare to become an AI Engineer that could apply to all those job postings we're seeing everywhere? What am I missing here?