Confusion understanding "coded-or-free-text-answer" file or tag

Hi, I’m a new developer working on a bug in the AllergyUI module and I have a few questions regarding the functionality of the code. The bug I’m looking to fix is located is in the text field within the “DRUG” section and so I’m interested to know what the coded-or-free-text answer does and it’s significance. Along with the purpose of the coded-or-free-text-answer.js file. I’ve included some images to show you what section I’m working on

A follow up question is why does the “DRUG” section use coded-or-free-text-answer while “FOOD” and “OTHER” do not?

Which ticket are you working on?

I found the bug myself while exploring the application and so I plan to submit a ticket. I’m just looking to get a better understanding of the code and specifically the coded-or-free-text file.

Having a ticket in place would help to give more context.