This section is written based on react-router v5 but the concepts are the same for most versions. The new react-router-v6 is out and has lots of cool new features. Most of the concepts are still the same, just a nicer API around them, so reading these notes will definitely be helpful but to go in depth into v6, you can read the docs 

Summary

Phylosophy

Router & Routes

URL Parameters

Nested Routes

Passing Props

Programmatically Navigate

Query Strings

404 Pages

Ambiguous Matches

Passing props to Link

Rendering a sidebar or Breadcrumbs with React Router v5

Active Links

Animated Transitions

Code Splitting

Protected Routes

Prevent Transitions

Route config

Client & Server Side rendering

Cannot get url error

Recursive paths with React Router v5

React Router: Declarative Routing for React

Routing: react-router

React Router: Declarative Routing for React