public sealed class Sandbox.Services.Inventory.Item

Editor UI is built entirely out of Widgets. Widgets are different from Panels, which are used for in-game UI. Widgets can be various elements or components, such as labels, buttons, text boxes, trees, or images.

Razor Component allow you to define some content to show inside another razor file. This makes it easy to create Panels that are more agile and reusable.

The Storage system provides a simple, unified way to manage user-generated content in your game. Whether you're saving game progress, storing player creations, or anything else, Storage handles everything from local file management to Steam Workshop integration.

VirtualGrid is a Panel that allows you to create a grid of items virtually. What this means is that if you have 1 million items, it won't render them and try to lay them all out at the same time. It'll just pick the few that are visible and create them. When you scroll down, it'll delete the ones it can no longer see and create the new visible ones.