Page 102 - TP_Play_V2.1_class8
P. 102
Tech Funda
For iris and retinal recognition, it is advisable to remove eye glasses and contact lenses.
(iii) Voice Recognition: The term voice recognition refers to identifying the person who
is speaking based on their unique voice characteristics, such as tone, pitch, and rhythm,
rather than interpreting the actual words spoken. Recognising the speaker can simplify
the task of translating speech into system that has been trained on a specific person’s
voice or it can be used to authenticate or verify the identity of a speaker as part of a
security process.
Encryption: Encryption is the process of converting data and information into a form,
called ciphertext, that cannot be easily understood by unauthorised people.
Decryption: It is the process of converting encrypted data back into its original form,
so that it can be understood.
The use of encryption/decryption is as old as the art of communication. In earlier times,
particularly during wars, a cipher, often referred to as a code, was used to prevent
enemies from accessing the contents of transmissions.
Simple ciphers include the substitution of letters for numbers, the rotation of letters
in the alphabet, and the ‘scrambling’ of voice signals by inverting the sideband
frequencies. Some complex ciphers work according to sophisticated computer
algorithms that rearrange the data bits in digital signals. For example, take a look at
the following code:
Jogpsnbujpo Qspufdujpo
Do you understand the code or does it make any sense? No. This is because it is
written in encrypted format. However, if you know the decryption method, you can
decrypt it.
Try replacing every letter in the message with the letter precedes it in the alphabet.
You will find that the code is:
Information Protection
HOW TO BACKUP YOUR IMPORTANT FILES?
In this section, you will learn how to back up your computer files. This is an important step in
ensuring the safety of your data. Have you ever lost any important documents, photos or other
files? Imagine what would happen if your computer suddenly stops working.
It may be possible to repair your computer, but your files might get lost forever. Fortunately,
you can prevent this by creating backup copies of all of your files (or just the important ones) on
an external hard disk drive or an online backup (Cloud Storage) service.
100 Play (Ver. 2.1)-VIII

