Databases often suffer from security problems when storing passwords. Plain text passwords cannot be stored in your database because then anyone who has access to the database would know the passwords of every user. The solution to this problem is to store encrypted passwords in a database. This is called password hashing.
As part of a general security concept, Hashing involves encoding a string according to the hashing algorithm used. MD4, MD5, SHA (Security Hashing Algorithm) like SHA256 SHA128, etc., are some of the hashing algorithms that can be applied. The hashing method should take the password as input and return a hashed string, which should be stored in a database rather than plain text.