What is mean by Hard-drive Encryption

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Encryption is basically the process of making any type of data unreadable by anyone without proper authorization. It will continue to be un-readable even after sharing it with other people it means only you with the right encryption key can make the data readable again.

How encryption works?

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Unencrypted data, often referred to as plaintext, is encrypted using an encryption algorithm and an encryption key. This process generates text that can only be viewed in its original form if decrypted with the correct key. Decryption is simply the inverse of encryption. Today's most widely used encryption algorithms fall into two categories: symmetric & asymmetric.

It is not just to stop the NSA from accessing your files, but it's more about preventing your private data from falling into the wrong hands if you lose your device, or gets stolen.

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What is TPM (chip)?

Trusted Platform  Module (TPM) chip. This is a special microchip that enables your device to support advanced security features.

The process to encrypt an entire hard drive or disk  is not difficult, but it's time-consuming. Depending the amount of data and size of the drive, it can take a very long time. Ensure that it is connected uninterupted power supply.

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Symmetric-key ciphers

It also referred to as "secret key," use a single key, sometimes referred to as a shared secret because the system doing the encryption must share it with any entity it intends to be able to decrypt the encrypted data. The most widely used symmetric-key cipher is the Advanced Encryption Standard (AES), which was designed to protect government classified information.

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Asymmetric cryptography

It is also known as public key cryptography, uses two different but mathematically linked keys, one public and one private. The public key can be shared with everyone, whereas the private key must be kept secret. The RSA encryption algorithm is the most widely used public key algorithm, because both the public and the private keys can encrypt a message,the opposite key from the one used to encrypt a message is used to decrypt it.