Programming
Programming is the stage of development where the actual game software is compiled. Programming encompasses everything related to putting the game together, from user interface implementation to scripting.
Typically, visual novel developers both indie and larger scale select an engine to develop their game software with. It is rare for a visual novel development team to create their own in-house engine from scratch.
Scripting
Scripting (also known as staging, direction, or enshutsu) is the act of inserting audiovisual cues into the game script. In its most basic form, scripting encompasses calling art assets to the screen and having sound and music stop or play, but can also include more involved things such as using the engine to animate images and adding visual effects.