Code Documentation Writer : Someone who writes any kind of documentation related to the code base.
Command Line Interface (CLI) : When a user types in commands to run a program or parts of a program, the user is using a “Command Line Interface”. On most computers this can be done using the Terminal. Often, the layer behind a Graphical User Interface (GUI) is command line based making it easy to test programmatically.
Generic Programmer : Someone who can read, write and repurpose the code base. This person is not the Code Author of code base.
Graphical User Interface (GUI) : Websites are a perfect example to understand Graphical User Interfaces. Without the imagery, buttons, input fields and text in different sizes, a website would simply be a big heap of text. In lieu of buttons, in a non-graphical interface, the user would have to enter a command. So basically a GUI, can be understood as a layer of graphics between the user and any commands a program understands. HTML is the most popular GUI markup language which wraps commands into browser-friendly tags. Browsers then interpret HTML markup display GUI which completely obfuscate the commands.
Team Member : Someone who is part of the same team as the Code Author.
Technical Writer : Someone who writes any kind of documentation.