GST registration is mandatory for businesses involved in the supply of goods or services in India, with an annual turnover exceeding Rs. 20 lakhs (Rs. 10 lakhs for special category states). It is a process of obtaining a unique Goods and Services Tax Identification Number (GSTIN) from the tax authorities.

The following are the steps involved in the GST registration process:

1. Visit the GST portal (https://www.gst.gov.in/) and click on the ‘Register Now’ button.
2. Fill in the required details such as your name, PAN, email address, and mobile number in Part-A of the registration form and submit it.
3. After submitting Part-A of the registration form, you will receive a Temporary Reference Number (TRN) on your mobile and email.
4. Use the TRN to log in to the GST portal and complete Part-B of the registration form.
5. Upload the necessary documents such as PAN, Aadhaar, bank statement, etc.
6. After submitting the application, the GST officer will verify the details and approve the application within 3 working days.
7. In case of any discrepancies, the GST officer may ask for additional documents or information.
8. Once the application is approved, you will receive the GST registration certificate, which contains your GSTIN.

It is important to note that the GST registration process may differ based on the type of entity, such as sole proprietorship, partnership firm, company, etc. Hence, it is advisable to seek professional assistance in case of any doubts or queries.