Game Engines
Also written as Unity, Unreal Engine, Godot, Game Development
Toolkits for building interactive 3D and 2D experiences, handling graphics, physics, sound and input. Unity (programmed in C#) and Unreal Engine (C++) dominate, and they're also used outside gaming for simulations, VR/AR training, film and automotive visualisation.
Think of it like
A film studio with sets, lighting and cameras already built, so the team can focus on the story.
Junior or senior?
Unity and Unreal skills don't fully swap: different languages, and Unreal is favoured for high-end graphics.
Senior sounds like
Has shipped a title or product and can talk about performance on the target hardware (frame rate, memory on console or mobile).
Ask them
“What did you ship with it, and what was the hardest performance problem on the target device?”