The main difference between an ITIN (Individual Taxpayer Identification Number) and an SSN (Social Security Number) lies in who is eligible to receive them and their primary purpose.
SSN (Social Security Number):
ITIN (Individual Taxpayer Identification Number):
In summary, if you are authorized to work in the U.S., you should obtain an SSN. If you are not eligible for an SSN but need to file U.S. taxes, you will need an ITIN.