[I originally asked this question on serverfault.com, where it was closed as 'out of scope.' Hopefully it is appropriate for this forum]

I am a developer who doesn't understand how to effectively manage Internet domain names.

Say I registered a name with namecheap and host a website on linode. Now what is an a-record? What is a name server and do I host it with namecheap of linode? Why would I pay amazon when others are free? Does any of this matter in terms of website latency or reliability?

I feel like a script kiddy, copying and pasting others' and hoping it works. Is there a book or other resource that explains all this? I know amazon is full of books about DNS, but afaik they are about setting up DNA servers for local networks, not the Internet.

p.s. To emphasize, I'm asking for books or long write-ups which explain this to technically competent people, who just haven't had to think about the role of commercial registrars, name servers, commercial hosts, commercial websites and how all parts play together on the real internet (not local networks).