Overview of Routinggrid
The routing grid is a unique parameter of the autorouter and completely separate from the normal working grids of the schematic and board editor. If you disable the Auto grid option then you get the option to define the routing grid yourself. The attached picture shows how you can have this setting. The lowest value it can have is 2mils.

Moving forward, it's essential to keep these visual contexts in mind when discussing Routinggrid.
As we can see from the illustration, Routinggrid has many fascinating aspects to explore.
Understanding Routinggrid Before the Gallery
MATLAB simulation of neighbour grid-based ring routing in multi-layer. This note connects the source idea with the visuals in a simple, reader-friendly way.
PPT - ASIC Back-End Design PowerPoint Presentation, free download - ID. It gives the article a little more context before the image collection begins.
Grid-Based placement, routing graph, and pin-shape of P-FET/N-FET using. It works as a short bridge between the article summary and the gallery section.
Looking at multiple sources also helps separate the main idea from small decorative details.
These notes are added so the page offers more than images and gives each visitor a clearer reason to keep reading.