Windows 7 - Ordinary password security while logging
Windows 8 - Ordinary password security while logging.
Windows 10 - Windows Hello, one of the security which lets you log-in using a fingerprint, face or iris scan instead of a password.

The different types of operating system uscd in the computer:
(i) Single User and Single Task Operating Systems
(ii) Multi User Operating Systems
(iii) Multi Pocessing Operating Systems
(iv) Distributed Operating Systems
(v) Prominent Operating Systems

1. BCD - Binary Coded Decimal.
2. EBCDIC - Extended Binary Coded Decimal Interchange Code.
3. ASCII - American Standard Code for Information Interchange,
4. Unicode.
5. ISCII - Indian Standard Code for Information Interchange

IBM 360 Series, Honeywell 6000 series.

(i) An OS is required to access and use the hardware resources.
(ii) It provides a stable, consistent way for applications to deal with the hardware.
(iii) An OS prepares the computer for taking instructions from the user and converts into machine code and gives into the CPU for execution.
(iv) as only co-ordinates and controls all the activities of a computer system.

(i) The address bus is used to point a memory location.
(ii) A decoder, a digital circuit is used to point to the specific memory location where the word can be located.
(iii) The address register is connected with the address bus, which provides the address of the instruction.
(iv) A data bus is used to transfer data between the memory and the CPU.
(v) The data bus is bidirectional and the address bus is unidirectional.
(vi) The control bus controls both read and write operations.
(vii) The system bus is a bunch of wires which is the collection of address bus, data bus and control bus that serves as communication channels between the microprocessor and other devices.

1) 0 +  0  = 0
2) 1 +  0 = 1  
3)  1+ 1 = 1
4) 0 + 1 = 1

Fingerprint scanner :
Fingerprint Scanners is a fingerprint recognition device used for computer security equipped with the fingerprint recognition module feature that uses biometric technology. Fingerprint Reader/Scanner is very safe and convenient device for security instead of password, that is vulnerable to fraud and is hard to remember.

(i) Computer is the powerful machine.
(ii) It can perform large number of tasks
(iii) The main capacities of computer are work length, speed accuracy, diligence, versatility memory and automation and lots of more tasks.

Log Off:
To log off from our computer:
(i) Click on the start button.
(ii) Select log off.
(iii) If any open programs asked to be closed then Windows force them to shut down. Any unsaved information will be last.

Shut Down:
To shut down our computer:
(i) Click on the start button.
(ii) Select shut down.
(iii) Then see the shut down windows dialog box opens.
(iv) If any open programs asked to be closed then Windows, force them to shut down. Any unsaved information will be lost.