What is the purpose of tags like :Name:, :Context:, etc. in packages?

I noticed that all of the packages that come with Mathematica start with a header that is in a standard format. (See e.g. the header of NIntegrateUtilities` at the end.)

There are several commented sections, each starting with a word surrounded by colons.

Question: What is the purpose of these colon-surrounded words? Do they have any meaning to Mathematica? They look like they were made for a machine to parse. Does Mathematica have any functions/tools that can read these?

(* :Name: NIntegrateUtilities` *)


(* :Title: Utility functions for NIntegrate. *)

(* :Author: Anton Antonov *)

(* :Summary:
 This package provides a number of supporting functions for NIntegrate.
*)

(* :Context: DifferentialEquations`NIntegrateUtilities` *)


(* :Package Version: 1.0 *)

(* :Copyright: Copyright 2007, Wolfram Research, Inc. *)

(* :History:
 Version 1.0 by Anton Atnonov, March 2007.
*)

(* :Keywords:
 NIntegrate, integration, evaluations, profiling.

*)

(* :Source:
*)

(* :Mathematica Version: 6.0 *)

(* :Limitation:
*)


(* :Discussion:
*)

Answer

Old versions of Mathematica featured the package Utilities`Package`. This had the function Annotation[] that read those commented lines in packages so that one could see those annotations without having to explicitly open those packages in the front end.

Needs["Utilities`Package`"]

Annotation["Statistics`NonlinearFit`"]
{"Title", "Context", "Name", "Author", "Summary", "Copyright", "Package Version", "Mathematica Version", "History", "Keywords", "Sources", "Discussion", "Warning", "Example", "Example", "Example"}


Annotation["Statistics`NonlinearFit`", "Mathematica Version"]
{"(* :Mathematica Version: 5.0 *)"}

If you want to still use this function, it's available here. I would say those specific delimiters allowed the package to pick out annotations instead of code comments.

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