Hashing in a Nutshell

The video tutorial explains hashing, a process of converting data into a fixed-length string that is irreversible. It covers the properties of hashes, their applications in file verification, password storage, and database searching. The tutorial also discusses common hash algorithms like SHA and MD5, and highlights the differences between hashing and encryption. Hashing is used for data integrity and security, but it is not meant for data encryption. The video also addresses the issue of hash collisions and their rarity.

What is the primary characteristic of a hash function?

• It can be easily reversed.

• It produces a fixed-length output.

• It is used to encrypt data.

• It always produces the same output for different inputs.

Which of the following is NOT a common use of hashing?

• Speeding up database searches

• Encrypting messages

• Storing passwords securely

• Verifying file integrity

Why is hashing preferred over plain text for storing passwords?

• It makes passwords longer.

• It makes passwords more memorable.

• It prevents passwords from being read if the database is compromised.

• It allows passwords to be easily retrieved.

How does hashing improve database search efficiency?

• By increasing the size of the database

• By storing data in plain text

• By reducing the length of data to be searched

• By encrypting the data

Which of the following is a characteristic of encryption but not hashing?

• It is a one-way function.

• It can be reversed to retrieve the original data.

• It produces a fixed-length output.

• It is used for data comparison.

What is a hash collision?

• When two different inputs produce the same hash

• When two identical inputs produce different hashes

• When a hash is longer than the input data

• When a hash cannot be generated

How can the likelihood of hash collisions be reduced?

• By using the same hash function for all data

• By using longer hash values

• By using shorter hash values

• By avoiding the use of hash functions