PRACTICAL - 103 :- HOW TO CREATE AND CONFIGURE USER ACCOUNTS IN WINDOWS XP,VISTA ,7/8

 

With Windows 7, everyone who uses your computer can have their own user account. This allows each person to have his or her own settings, and it allows you to set up Parental Controls to limit the types of games and programs your children are able to use.

Why should you have multiple user accounts?

If you wanted to, you could have a single account on your computer that everyone could use. But having multiple accounts has some advantages. If each user has his or her own account, then each person will have his or her own desktop for organizing files and folders. Each person also will be able to choose a specific desktop background, along with other personalization features. In addition, parents will be able to set Parental Controls for each child's account.

Standard vs. administrator accounts

Before you start making new user accounts, it's important to understand the two types of accounts:

1. Standard: Standard accounts are the basic accounts you use for normal, everyday tasks. As a Standard user, you can do just about anything you would need to do, such as running software or personalizing your desktop. Also, Parental Controls can be placed on Standard accounts.
2. Administrator: Administrator accounts are special accounts that are used for making certain changes to system settings or managing other people's accounts. They have full access to every setting on the computer. Every computer will have at least one Administrator account.

As you can see, Administrator accounts are more powerful. But for the same reason, Standard accounts are safer, so they are generally better for everyday use. In fact, you can make Administrator-level changes while logged into a Standard account; you will just need to provide an Administrator password when making the changes.

To go to your user accounts:

1. Go to the Control Panel from the Start Menu.
2. Click Add or remove user accounts.
   
   
   
3. The Manage Accounts pane will appear. You will see all of the user accounts here, and you can add more accounts or manage existing ones.
   
   
   

To create a new account:

1. From the Manage Accounts pane, click Create a new account.
2. Type an account name.
   
   
   
3. Select Standard user or Administrator.
4. Click Create Account.

Changing an account's settings

Once you've created a new account, you may want to add a password or make other changes to the account's settings.

To create a password:

1. From the Manage Accounts pane, click the account name or picture.
   
   
   
2. Click Create a password.
   
   
   
   
3. Type a password in the New password field, and retype it in the Confirm new password field. 
4. If you want, you can type a password hint to help you remember your password.
5. Click Create password.
6. To go back to the Manage Accounts pane, click Manage another account.

• Account passwords are case sensitive, which means capital and lowercase letters are treated as different characters. For example, aBc1 is not the same as abc1.

To change your account picture:

You can also change the picture for any account. This picture appears next to the account name and helps you easily identify the account

1. From the Manage Accounts pane, click the account name or picture.
2. Click Change the picture.  
3. Select a picture, or click Browse for more pictures to select one of your own. 
4. Click Change Picture.

Conclusion

You can now create new accounts whenever you want, and all users will be able to easily access their own files and customize the appearance of Windows 7 while they're logged in to their respective accounts.

PRACTICAL - 104 :- HOW TO VIEWS HIDDEN FILES AND FOLDERS

How to Show Hidden Files in Windows 10

By default, Microsoft Windows 10 hides certain files from view when you explore them on your hard drive. This protects important files from being deleted so that the system isn’t damaged. If you’ll want to be able to view all files all the time. Follow these steps to show hidden files.

Option 1 – From File Explorer

1. Select the “Start” button, then choose “File Explorer“
2. Make sure the menu bar is expanded. You can toggle the menu bar by selecting the ^ at the upper right portion of the window.
3. Select the “View” tab.
4. Check the “Hidden items” check box to view hidden items.
5.  If you need more file viewing options, select “Options” > “View“.
   

Option 2 – From Control Panel

1. Right-click the “Start” button, then select “Control Panel“.
2. Go to “Appearance and Personalization“, then select “File Explorer Options“.
3. Click the “View” tab.
4. Scroll down a bit and change the “Hidden files and folders” setting to “Show hidden files, folders, and drives“. Optionally, you may wish to uncheck the “Hide protected operating system files” box as well.

Option 3 – Via Registry

1. Hold the Windows Key and press “R” to bring up the Run dialog box.
2. Type “regedit“, then press “Enter“.
3. Navigate to the following location:                                                                                                                          ·         HKEY_CURRENT_USER

   ·         Software

   ·         Microsoft

   ·         Windows

   ·         CurrentVersion

   ·         Explorer

   ·         Advanced
   

4. Set the value for “Hidden” to “1” to show hidden files, folders, and drives. Set the value to “2” to not show hidden files, folders, and drives.
5. Set the value for “ShowSuperHidden” to “1” to show protected operating system files. Set the value to “2” to not show protected operating system files.

    

 

 

THEORY- 100 :- DVD - HISTROY, CATEGORIES, PARTS AND WORKING

 DVD 

What is the Full form of DVD?

The full form of DVD is Digital Versatile Disc. DVD is a digital optical disc storage format which was developed and invented in 1995 and used to store high-capacity files, such as top-standard videos and movies. VCDs were standard optical digital storage disks before invention, but DVDs have higher capacity than compact discs of almost the same size and shape.

The unofficial full name of DVD also existed and it was named Digital Video Disc. But as DVDs were not merely restricted to videos, mass technology forums denied this full term. In 1995 Four companies called Sony, Philips, Sony, Panasonic and Toshiba discovered and developed it.

History of DVD

• The DVD was first developed to replace VHS tapes but soon became famous as a storage device.
• In 1972 Audio-CD was established as an entertainment tool.
• In 1993, two types of video disks were developed, the MMCD (Multimedia Compact Disc), and the SD (Super Density).

Categories of DVD

A DVD comes in two different sizes.

• DVD with a size of 120 mm – Used for software, videos, and operating system storage and so on.
• DVD with a size of 80 mm – Used for compact devices such as portable music player & video camera etc.

DVDs are classified depending on their operation such as

• DVD-ROM can be used only for reading, but it cannot be written.
  
  
• DVD-R is used for recording data of any kind.
• DVD-RW is Readable, writable and can be deleted & rewritten.

Benefits of DVD

• High capacity storage, for example, 4.7 – 9 Gb.
• Great quality of sound and picture, so the correct approach to store videos & audios.
• Relatively inexpensive, because they are manufactured in mass production.
• Like CD, data can be preserved on both sides of the DVD.

Parts of a DVD Player

 

The DVD player is not only used for playing the data present in a DVD, but also to write the content onto a DVD. To know this process it is essential to know the basics of a DVD.

As told earlier, DVD’s have pits and bumps in their track which holds the information that is required to be played. This information can be a video, audio or a mixture of both. When a DVD player reads this data, the smooth surface is usually taken as a ‘0’ and pits are usually taken as a ‘1’.

In order to create as well as read these data, a red laser with a wavelength of 600 nanometers. This is about 180 nanometers lesser than the wavelength of CD, which enables it to have a higher density of pits. Thus the size of the DVD increases. Though the first released DVD’s were only a single layer, 2 layered discs have been released nowadays. Single layer can hold only up to 4.7 GB of data while double layered DVD can hold up to 17 GB of data. The DVD design is similar to a CD a reflective silver layer in the centre and a semi-transparent gold layer on the top of it.

A DVD does not have the capacity to hold hi-def movies. So a MPEG-2 compression system is introduced. As this is used, the data will be encoded onto the DVD as elements of the changing frames. This has to be successfully decoded and decompressed by the DVD player.

Thus the parts of a DVD player are

 

1. Disc drive mechanism

The disc drive mechanism consists of a motor that will drive the disc in a circular motion. The mechanism will also have a disc feed – a loading tray that is used to accept the DVD from the user. Thus the entire disc drive is basically a spindle that holds the disc and a motor that is used to circle the disc. The spindle is held in its position with the help of small gears and belts that are attached internally. Some players have an automatic feed system in which, there will be no tray. Instead the disc will be automatically recognized after inserting a part of it.

2. Optical system

The optical system mainly consists of the laser beam, lenses, prism, photo-detectors and also mirrors. The output of this mechanism will be the input for the disc-drive. The laser beam will be a red laser diode which works at a wavelength of 600 nanometers. The optical system also requires a motor to drive it. The laser system and photo-detector is placed together on a single platform. The laser diode as well as other diodes is made with the help of glass.

3. Printed Circuit Board

The PCB is similar to that of any other electronic circuits. The electronic outline must be drawn on the PCB with the correct placement of all the IC’s resistors as well as capacitors. After the outline has been drawn, the components must be soldered to their respective places. All this must be done in a very clean environment so that the board does not become contaminated by dust. All the primary components of the electronic circuit should be made out of silicon.

 

Working of DVD Player

 

Take a look at the basic block diagram of how a DVD player works.

 

The pits and bumps in the DVD are hit by the laser from the optical mechanism of the DVD player. This laser will be reflected differently according to the change of pits and bumps. Though the laser hits a single spot, the DVD moves in a circular motion so that the entire area is covered. Mirrors are also used to change the spot.

 

These reflected laser beams are then collected by a light sensor (eg. photo-detector) which converts the different signals into a binary code. In short, the optical system helps in converting the data from the DVD into a digital code.

 

The binary signal is then sent to a Digital to Analog converter which will be setup in the PCB. Thus the corresponding analog signal of the DVD is obtained. The PCB also has amplifiers which amplify the signal and then sends it to the graphic and audio systems of the computer/TV. Thus, the corresponding audio/video signal is obtained. The basic working of a DVD player is shown below.

Assembling a DVD Player

As the different parts of the DVD player are all complicated electronic circuits, they are all manufactured by different people. They are later brought together and assembled at one place. During the assembling, the PCB will be connected to the rest of the machine and all the components are placed in the right positions. The whole package is then placed inside an outer plastic housing with a front panel with the buttons for various operations. This DVD player is then sent to a packaging station where they are placed safely inside boxes along with the

respective power cords, operating manual, installing disks and so on. They are then taken by the distributors to various shops and then sold to customers.

 

 

THEORY - 100.1 :- COMPACT DISK

 What is a CD?

A compact disc is a thin, circular disc of metal and plastic about 12cm (just over 4.5 inches) in diameter. It's actually made of three layers. Most of a CD is made from a tough, brittle plastic called polycarbonate. Sandwiched in the middle there is a thin layer of aluminum. Finally, on top of the aluminum, is a protective layer of plastic and lacquer. The first thing you notice about a CD is that it is shiny on one side and dull on the other. The dull side usually has a label on it telling you what's on the CD; the shiny side is the important part. It's shiny so that a laser beam can bounce off the disc and read the information stored on it.

What is the full form of CD?

The full form of CD is the compact disc. It is a flat, tiny-rounded storage unit that can store information of up to 700 mb and 4.75 inches in diameter. It is compact, so it is possible to carry wherever. Because its consistency does not degrade with time & long duration, we could operate it countless time. CDs can store digital formats of any information, such as video, audio, text, photographs, and so on. The data is stored on the disc in the form of tiny notches, and when the disc is performed, the information is interpreted from an optical drive by a laser.

Who invented CDs?

The technology behind CDs was invented in the late 1960s by James T. Russell (1931–). An avid music fan, he longed for a sound-recording system that would reproduce music more exactly than LP records and cassette tapes. He patented the first ever optical sound recording system in 1970, refining it over the years that followed. Audio CDs finally made their commercial debut in Europe in 1982, launched by the Sony and Philips electronics corporations,

A CD was later allowed to store collections of information on its disc as technology advanced. The compact disc then named as CD-ROM(Compact Disk-Read Only Memory).

The information stored only has the read operation but not the writing process. The very first CD audio player was made available to the public in Japan by Sony company.

Characteristics of CD

A CD’s characteristics involve:

• A regular Compact Disc has a diameter of around 120 millimeters (mm) and a width of 1.2 millimeters (mm).
• It consists entirely of plastic and has a shiny, glossy appearance.
• It just weighs up to 15 or 20 gram.
• A CD’s storage space is up to 700 MiB, that ensures that a Compact Disc can operate up to 80 minutes of sound quality.
• Types of compact discs
• The Compact Disc-Read Only Memory (CD-ROM) is a common and standard optical disc used during computer data processing.
• Recordable Compact Disc (CD-R) has a write process option. It is made of quality dye that, as light strikes on it, reflects various colors. The CD-R has a life span of 20 to 100 years.
• The Rewritable Compact Disc (RW-CD) is a disc where material can be removed and rewritten over and over again.
• The Video Compact Disc(VCD) helps you to see a moving picture on the screen easily.

Benefits of CD

• In terms of size, it is tiny.
• It is a portable device.
• Access to Data Faster.
• It is inexpensive to manufacture.

Limitation of CD

• It has a smaller storage capacity.

It can create scratches when it is used quite frequently.

DAYWISE

 

Theory - 104 :- Concept Of Virtual Machine

 

What is a virtual machine?

A Virtual Machine (VM) is a compute resource that uses software instead of a physical computer to run programs and deploy apps. One or more virtual “guest” machines run on a physical “host” machine.  Each virtual machine runs its own operating system and functions separately from the other VMs, even when they are all running on the same host. This means that, for example, a virtual MacOS virtual machine can run on a physical PC.

Virtual machine technology is used for many use cases across on-premises and cloud environments. More recently, public cloud services are using virtual machines to provide virtual application resources to multiple users at once, for even more cost efficient and flexible compute. 

What are virtual machines used for?

Virtual machines (VMs) allow a business to run an operating system that behaves like a completely separate computer in an app window on a desktop. VMs may be deployed to accommodate different levels of processing power needs, to run software that requires a different operating system, or to test applications in a safe, sandboxed environment.  

Virtual machines have historically been used for server virtualization, which enables IT teams to consolidate their computing resources and improve efficiency. Additionally, virtual machines can perform specific tasks  considered  too risky to carry out in a host environment, such as accessing virus-infected data or testing operating systems. Since the virtual machine is separated from the rest of the system, the software inside the virtual machine cannot tamper with the host computer. 

How do virtual machines work?

The virtual machine runs as a process in an application window, similar to any other application, on the operating system of the physical machine. Key files that make up a virtual machine include a log file, NVRAM setting file, virtual disk file and configuration file. 

Advantages of virtual machines

Virtual machines are easy to manage and maintain, and they offer several advantages over physical machines:   

• VMs can run multiple operating system environments on a single physical computer, saving physical space, time and management costs. 
• Virtual machines support legacy applications, reducing the cost of migrating to a new operating system. For example, a Linux virtual machine running a distribution of Linux as the guest operating system can exist on a host server that is running a non-Linux operating system, such as Windows. 
• VMs can also provide integrated disaster recovery and application provisioning options.  

Disadvantages of virtual machines

While virtual machines have several advantages over physical machines, there are also some potential disadvantages: 

• Running multiple virtual machines on one physical machine can result in unstable performance if infrastructure requirements are not met. 
• Virtual machines are less efficient and run slower than a full physical computer. Most enterprises use a combination of physical and virtual infrastructure to balance the corresponding advantages and disadvantages. 

The two types of virtual machines

Users can choose from two different types of virtual machines—process VMs and system VMs:  

• A process virtual machine allows a single process to run as an application on a host machine, providing a platform-independent programming environment  by masking the information of the underlying hardware or operating system. An example of a process VM is the Java Virtual Machine, which enables any operating system to run Java applications as if they were native to that system.   
• A system virtual machine is fully virtualized to substitute for a physical machine. A system platform supports the sharing of a host computer’s physical resources between multiple virtual machines, each running its own copy of the operating system. This virtualization process relies on a hypervisor, which can run on bare hardware, such as VMware ESXi, or on top of an operating system.  

 What are 5 types of virtualization?

All the components of a traditional data center or IT infrastructure can be virtualized today, with various specific types of virtualization:   

Hardware virtualization: When virtualizing hardware, virtual versions of computers and operating systems (VMs) are created and consolidated into a single, primary, physical server. A hypervisor communicates directly with a physical server’s disk space and CPU to manage the VMs. Hardware virtualization, which is also known as server virtualization, allows hardware resources to be utilized more efficiently and for one machine to simultaneously run different operating systems. 

 

Software virtualization: Software virtualization creates a computer system complete with hardware that allows one or more guest operating systems to run on a physical host machine. For example, Android OS can run on a host machine that is natively using a Microsoft Windows OS, utilizing the same hardware as the host machine does. Additionally, applications can be virtualized and delivered from a server to an end user’s device, such as a laptop or smartphone. This allows employees to access centrally hosted applications when working remotely. 

 

Storage virtualization: Storage can be virtualized by consolidating multiple physical storage devices to appear as a single storage device. Benefits include increased performance and speed, load balancing and reduced costs. Storage virtualization also helps with disaster recovery planning, as virtual storage data can be duplicated and quickly transferred to another location, reducing downtime.  

 

Network virtualization: Multiple sub-networks can be created on the same physical network by combining equipment into a single, software-based virtual network resource. Network virtualization also divides available bandwidth into multiple, independent channels, each of which can be assigned to servers and devices in real time. Advantages include increased reliability, network speed, security and better monitoring of data usage. Network virtualization can be a good choice for companies with a high volume of users who need access at all times. 

 

Desktop virtualization: This common type of virtualization separates the desktop environment from the physical device and stores a desktop on a remote server, allowing users to access their desktops from anywhere on any device. In addition to easy accessibility, benefits of virtual desktops include better data security, cost savings on software licenses and updates, and ease of management. 

 

Introduction to Types of Computer Language

Introduction to Types of Computer Language

The computer language is defined as code or syntax which is used to write programs or any specific applications. The computer language is used to communicate with computers. Broadly the computer language can be classified into three categories assembly language, machine language, and high-level language. The machine language is considered as oldest computer language among all three. In machine language, the input is directly given as binary input which is processed by the machine. Binary inputs mean one and zero form. For computer language processing the system needs compiler and interpreter to convert the language in computer language so that it can be processed by a machine

.

Different Types of Computer

Machine Language

The machine language is sometimes referred to as machine code or object code which is set of binary digits 0 and 1. These binary digits are understood and read by a computer system and interpret it easily. It is considered a native language as it can be directly understood by a central processing unit (CPU). The machine language is not so easy to understand, as the language uses the binary system in which the commands are written in 1 and 0 form which is not easy to interpret. There is only one language which is understood by computer language which is machine language. The operating system of the computer system is used to identify the exact machine language used for that particular system.

The operating system defines how the program should write so that it can be converted to machine language and the system takes appropriate action. The computer programs and scripts can also be written in other programming languages like C, C++, and JAVA. However, these languages cannot be directly understood by a computer system so there is a need for a program that can convert these computer programs to machine language. The compiler is used to convert the programs to machine language which can be easily understood by computer systems. The compiler generates the binary file and executable file. 

Example of machine language for the text “Hello World”.

01001000 0110101 01101100 01101100 01101111 00100000 01010111 01101111 01110010 01101100 01100100.

 

Assembly Language

The assembly language is considered a low-level language for microprocessors and many other programmable devices. The assembly language is also considered as second-generation language. The first generation language is machine language. The assembly language is mostly famous for writing an operating system and also in writing different desktop applications. The operations carried out by programmers using assembly language are memory management, registry access, and clock cycle operations. The drawback of assembly language is the code cannot be reused and the language is not so easy to understand. The assembly language is considered a group of other languages. It is used to implements the symbolic representation of machine code which is used to program CPU architecture. The other name of assembly language is assembly code. For any processor, the most used programming language is assembly language.

In assembly language, the programmer does the operation which can be directly executed on a central processing unit (CPU). The language has certain drawbacks as it does not contain any variables or functions in programs and also the program is not portable on different processors. The assembly language uses the same structure and commands which machine language does use but it uses names in place of numbers. The operations performed using the assembly language is very fast. The operations are much faster when it is compared to high-level language.

 

High-Level Language

The development of high-level language was done when the programmers face the issue in writing programs as the older language has portability issues which mean the code written in one machine cannot be transferred to other machines. Thus lead to the development of high-level language. The high-level language is easy to understand and the code can be written easily as the programs written are user-friendly in a high-level language. The other advantage of code written in a high-level language is the code is independent of a computer system which means the code can be transferred to other machines. The high-level of language uses the concept of abstraction and also focus on programming language rather than focusing on computer hardware components like register utilization or memory utilization.

 

The development of higher-level language is done for a programmer to write a human-readable program that can be easily understood by any user. The syntax used and the programming style can be easily understood by humans if it is compared to low-level language. The only requirement in a high-level language is the need of compiler. As the program written in a high-level language is not directly understood by the computer system. Before the execution of high-level programs, it needs to be converted to machine level language. The examples of high-level language are C++, C, JAVA, FORTRAN, Pascal, Perl, Ruby, and Visual Basic.

1. JAVA: The JAVA programming language is an object-oriented language that is based on objects and classes. The main motto of the development of this language is to make a computer program run on any system. The JAVA code is machine-independent code means the code needs to be written once and can be executed on any machine. The memory management is done automatically in the java programming language.
2. C: The C is a procedural and general-purpose programming language used for writing programs. This language is mostly used for writing operating system applications and desktop applications.
3. PASCAL: The Pascal is a procedural programming language which is based on data structures. It uses the concept of recursive data structures such as graphs, lists, and graphs.