This is one of the cool secrets. If you want to correct light leakage or light artifacts, or you want to have more control over light and shadow, or you want
Negative light and emission in Blender
Subtract shaders - no longer works, but new sheen node can get pretty close - Materials and Textures - Blender Artists Community
Negative light and emission in Blender : r/blender
In Blender 4.0 border of Point Light is visible if intersect with geometry - Lighting and Rendering - Blender Artists Community
What is the Emission node in Blender 3D, and how is it used? - Quora
The difference between the holdout and transparency shader. I created a list containing 70+ sites with free resources for 3D artists. You can download
3D lights and shadows — Godot Engine (stable) documentation in English
Cycles Mesh Emission Too Noisy For Production - Lighting and Rendering - Blender Artists Community
Why use Blender's 'lights' over just a mesh with emission? - Lighting and Rendering - Blender Artists Community
Negative light and emission in Blender : r/blender
materials - Emission based on volume - Blender Stack Exchange