Need some clarification on Authorization in OAuth in Twitter

[TestDashboardAc]

Hi Team,

I have Registered my twitter application for OAuth process and got the ConsumerID and Consumer Secret key. I have referred the authorization process in your documentation (https://developer.twitter.com/en/docs/basics/authentication/overview/oauth). In this, they provided the four kinds of Authorization.

1. Application-only authentication.
2. Basic authentication
3. 3-legged OAuth
4. PIN-Based OAuth

Please let me know the details of each authorization process and its OAuth version type.

whether the 3-legged OAuth process is available in OAuth 2.0? If not, when will this support is available.

Thanks,
Anand