Easy Auth Question 47 of 226

Why must passwords be hashed before they are stored?

MERN Full Stack · Speak this in 60–90 seconds · Faridabad & Delhi NCR

PICTURE THIS: DATABASE INDEX

Without indexScan every row

With indexJump to keys

CostWrites slower

Simple meaning

Hashing turns a password into a one-way digest so a database leak does not reveal real passwords.

WHY — Auth instead of guessing?

Why interviewers care about Auth:

They are checking judgment

on Auth.

A good answer names

the situation, the default choice, and one exception - that reads as experience.

Stay structured

Name the idea, why it exists, then one short example.

Close cleanly

End with when you use it and one common pitfall.

STEPS — What happens step by step?

Before you speak the answer, walk the interviewer through these steps:

1
Hashing turns a password
into a one-way digest so a database leak does not reveal real passwords.
2
Use a slow salted
algorithm such as bcrypt or argon2, never a fast hash like MD5.
3
The server stores the
hash and compares hashes at login.
4
Give an example
One tiny concrete case you can say aloud.
5
Common mistake
What juniors usually get wrong.
6
Close
When you pick this over the alternative.

EXAMPLE — See it in action

Here's a short line you can speak, broken into clear beats:

Say this line

“Use a slow salted algorithm such as bcrypt or argon2, never a fast hash like MD5”

Break into beats

Useaslowsaltedalgorithmsuch

Speaking order

2987408337471632900

Note: Adapt this scaffold to your own project — keep it under 60–90 seconds.

Key takeaway

Hashing turns a password into a one-way digest so a database leak does not reveal real passwords. Use a slow salted algorithm such as bcrypt or argon2, never a fast hash like MD5.