Github Personal Access Tokens

A Personal Access Token (PAT) is a credential used in place of a password when authenticating to GitHub over HTTPS or the API. Fine-grained tokens can be scoped to specific repositories and permissions.

Basic usage

Create one under Settings > Developer settings > Personal access tokens, then use it as the password when Git prompts:

git clone https://github.com/<user>/<repo>.git
Username: <user>
Password: <paste token>

Or with the API:

curl -H "Authorization: Bearer <token>" https://api.github.com/user

Source

GitHub Docs — Managing personal access tokens