The major difference between the two is that a hard pull appears on your credit report
while a soft pull does not.
When you apply for a line of credit, whether a new credit card, mortgage, auto loan, or
some other type of loan, the lender will pull your credit report from at least one of the major three credit reporting agencies — Equifax, Experian, and TransUnion, this is called a hard pull or a hard inquiry. A hard pull results in the lender getting your official credit report and credit score from whichever bureau it requested the information. This is a much more in-depth look at your credit history than what might be collected and sent over after a soft pull.
A soft inquiry, on the other hand, does not appear on your credit report and does not
affect your score at all. Soft pulls generally occur when you check your credit score, or you give someone like a potential employer permission to review your credit report. Generally speaking, a soft pull won’t result in someone receiving your full credit profile and score. Instead, he or she might get an estimated score based on the information requested or may get limited information pertaining to just one area of your report. These credit checks are not tied directly to a credit application of any kind, which is why they aren’t recorded in your report and do not affect your credit score.