What is an OAuth Grant Type?

The OAuth Grant Type determines the exact sequence of steps that are involved in the OAuth process. It also affects how the client application communicates with the OAuth service at each stage, including how the access token itself is sent. For this reason, grant types are often referred to as "OAuth flows".

The most common OAuth Grant Types are :

a) Authorization Code: It is used by confidential and public clients to exchange an authorization code for an access token. After the user returns to the client via the redirect URL, the application will get the authorization code from the URL and use it to request an access token.

b) Client Credentials: It is used by clients to obtain an access token outside of the context of a user. This is typically used by clients to access resources about themselves rather than to access a user's resources.

c) Device Code: It is used by browserless or input-constrained devices in the device flow to exchange a previously obtained device code for an access token.

d) Refresh Token: It is used by clients to exchange a refresh token for an access token when the access token has expired. This allows clients to continue to have a valid access token without further interaction with the user.