difference between users and roles in database

Discuss, in your own words using 500 words or more, the relationship between users and roles in databases. Explain why we use roles rather than simply assigning rights and privileges to each individual user. Consider how to handle new hires and job changes.
Cite your sources in-line and at the end. Provide a URL for your citations.  Write in essay format not in bulleted, numbered or other list format. Do not copy without providing proper attribution. Be aware of your Safeassign score. Over 30 is too high. Use quotes to indicate where you have used other’s words. 
Use the five paragraph format. Each paragraph must have at least five sentences. Include 3 quotes cited in-line and in a list of references. Include an interesting meaningful title.
It is important that you use your own words, that you cite your sources, that you comply with the instructions regarding length of your paper. Do not use spinbot or other word replacement software. It usually results in nonsense and is not a good way to learn anything. Please do not use attachments unless requested.