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Basics Of Html

What is HTML?
HTML is the standard markup language for creating Web pages.

HTML stands for Hyper Text Markup Language
HTML describes the structure of Web pages using markup
HTML elements are the building blocks of HTML pages
HTML elements are represented by tags
HTML tags label pieces of content such as "heading", "paragraph", "table", and so on
Browsers do not display the HTML tags, but use them to render the content of the page

Basics Of Html

What is HTML?
HTML is the standard markup language for creating Web pages.

HTML stands for Hyper Text Markup Language
HTML describes the structure of Web pages using markup
HTML elements are the building blocks of HTML pages
HTML elements are represented by tags
HTML tags label pieces of content such as "heading", "paragraph", "table", and so on
Browsers do not display the HTML tags, but use them to render the content of the page

Introduction To MS-DOS

MS-DOS (Microsoft Disk Operating System) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and some operating systems attempting to be compatible with MS-DOS, are sometimes referred to as "DOS" (which is also the generic acronym for disk operating system). MS-DOS was the main operating system for IBM PC compatible personal computers during the 1980s and the early 1990s, when it was gradually superseded by operating systems offering a graphical user interface(GUI), in various generations of the graphical Microsoft Windows operating system.

MS-DOS was the result of the language developed in the seventies that was used by IBM for its mainframe operating system. Microsoft acquired the rights to meet IBM specifications. IBM licensed and re-released it on August 12, 1981 as PC DOS 1.0 for use in their PCs. Although MS-DOS and PC DOS were initially developed in parallel by Microsoft and IBM, the…

Motherboard Components

Expansion slots (PCI Express, PCI, and AGP)
3-pin case fan connectors
Back pane connectors
Heat sink
4-Pin (P4) power connector
Inductor
Capacitor
CPU Socket
Northbridge
Screw hole
Memory slot
Super I/O
Floppy connection
ATA (IDE) disk drive primary connection
24-pin ATX power Supply connector
Serial ATA connections
Coin cell battery (CMOS backup battery)
RAID
System panel connectors
FWH
Southbridge
Serial port connector
USB headers
Jumpers
Integrated circuit
1394 headers
SPDIF
CD-IN


Older motherboard components
The following list contains some more components.


BIOS
Bus
Cache memory
Chipset
Diode
Dip switches
Electrolytic
Fuse
Game port and MIDI header
Internal speaker
Keyboard controller
LCC
Network header
Obsolete expansion slots (AMR, CNR, EISA, ISA, VESA)
Obsolete memory slots (SIMM)
Onboard LED
Parallel port header
PS/2 header
Resistor
RTC
Serial port header
Screw hole aka mounting hole
SCSI
Solenoid
Voltage regulator
Voltage regulator module (VRM)

Interfacing

In computing, an interface is a shared boundary across which two or more separate components of a computer systemexchange information. The exchange can be between software, computer hardware, peripheral devices, humans and combinations of these. Some computer hardware devices, such as a touchscreen, can both send and receive data through the interface, while others such as a mouse or microphone may only provide an interface to send data to a given system.


Hardware interfaces
Hardware interfaces exist in many of the components, such as the various buses, storage devices, other I/O devices, etc. A hardware interface is described by the mechanical, electrical and logical signals at the interface and the protocol for sequencing them (sometimes called signaling). A standard interface, such as SCSI, decouples the design and introduction of computing hardware, such as I/O devices, from the design and introduction of other components of a computing system, thereby allowing users and manufacture…

Hard disk Drive : Full Guide

hard disk drive (HDD), hard diskhard drive, or fixed disk, is an electromechanical data storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks (platters) coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces.[2] Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially. HDDs are a type of non-volatile storage, retaining stored data even when powered off.

Introduced by IBM in 1956, HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s. Continuously improved, HDDs have maintained this position into the modern era of servers and personal computers. More than 200 companies have produced HDDs historically, though after extensive industry consolidation most units are…

What Is Data Encoding?

Encoding is the process of converting the data or a given sequence of characters, symbols, alphabets etc., into a specified format, for the secured transmission of data. Decoding is the reverse process of encoding which is to extract the information from the converted format.
Data Encoding
Encoding is the process of using various patterns of voltage or current levels to represent 1s and 0s of the digital signals on the transmission link.

The common types of line encoding are Unipolar, Polar, Bipolar, and Manchester.
Encoding Techniques
The data encoding technique is divided into the following types, depending upon the type of data conversion.

Analog data to Analog signals − The modulation techniques such as Amplitude Modulation, Frequency Modulation and Phase Modulation of analog signals, fall under this category.
Analog data to Digital signals − This process can be termed as digitization, which is done by Pulse Code Modulation (PCM). Hence, it is nothing but digital modulation. As we have a…

How Does a Computer Mouse Work?

The public first saw a computer mouse when it was attached to the Macintosh computer in 1984. The Mac and its accompanying mouse had their debut at the half-time show of the Superbowl. A few years prior to this event, Steve Jobs, co-founder of Apple Computer, was allowed to visit and tour Xerox's research (PARC) facility in California, and noticed this funny-looking thing that was used to move the cursor around the screen of a computer. This was a revolutionary idea, since prior to this the keyboard arrow keys were the only way to navigate a computer screen. Jobs 'borrowed' the idea, and designed his own mouse to accompany the unveiling of his new Macintosh to the public. Then Microsoft picked up on it when they released their version of a graphical user interface (Windows) to make things even easier, and the rest, as they say, is history. The first types of mice were mostly mechanical, a ball rolled around under the body of the mouse, and rollers sensed the direction and …

How Does a Computer Keyboard Work?

The current keyboard layout, or the QWERTY layout, which is based on the layout of the typewriter, was designed not to increase the speed of typing, but to slow it down in order to avoid typewriters from jamming.

Computer Security

Computer securitycybersecurity, or IT security is the protection of computer systems from theft or damage to their hardware, software or electronic data, as well as from disruption or misdirection of the services they provide.

The field is growing in importance due to increasing reliance on computer systems, the Internet and wireless networks such as Bluetoothand Wi-Fi, and due to the growth of "smart" devices, including smartphones, televisions and the various tiny devices that constitute the Internet of Things. Due to its complexity, both in terms of politics and technology, it is also one of the major challenges of the contemporary world.


Vulnerabilities and Attacks
Main article: Vulnerability (computing)
A vulnerability is a weakness in design, implementation, operation or internal control. Most of the vulnerabilities that have been discovered are documented in the Common Vulnerabilities and Exposures (CVE) database.

An exploitable vulnerability is one for which at least on…

The Internet

The Internet is the global system of interconnected computer networks that use the Internet protocol suite (TCP/IP) to link devices worldwide. It is a network of networks that consists of private, public, academic, business, and government networks of local to global scope, linked by a broad array of electronic, wireless, and optical networking technologies. The Internet carries a vast range of information resources and services, such as the inter-linked hypertext documents and applications of the World Wide Web (WWW), electronic mail, telephony, and file sharing.

The origins of the Internet date back to research commissioned by the federal government of the United States in the 1960s to build robust, fault-tolerant communication with computer networks. The primary precursor network, the ARPANET, initially served as a backbone for interconnection of regional academic and military networks in the 1980s. The funding of the National Science Foundation Network as a new backbone in the 1980…

Local Area Network (LAN)

local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building. By contrast, a wide area network (WAN) not only covers a larger geographic distance, but also generally involves leased telecommunication circuits.

Ethernet and Wi-Fi are the two most common technologies in use for local area networks. Historical technologies include ARCNET, Token ring, Econet and AppleTalk.

Printers

A printer is a device that accepts text and graphic output from a computer and transfers the information to paper, usually to standard size sheets of paper. Printers vary in size, speed, sophistication, and cost. In general, more expensive printers are used for higher-resolution color printing.





Personal computer printers can be distinguished as impact or non-impact printers. Early impact printers worked something like an automatic typewriter, with a key striking an inked impression on paper for each printed character. The dot-matrix printer was a popular low-cost personal computer printer. It's an impact printer that strikes the paper a line at a time. The best-known non-impact printers are the inkjet printer, of which several makes of low-cost color printers are an example, and the laser printer. The inkjet sprays ink from an ink cartridge at very close range to the paper as it rolls by. The laser printer uses a laser beam reflected from a mirror to attract ink (called toner ) to …

Input & Output

In computing, input/output or I/O (or, informally, io or IO) is the communication between an information processing system, such as a computer, and the outside world, possibly a human or another information processing system. Inputs are the signals or data received by the system and outputs are the signals or data sent from it. The term can also be used as part of an action; to "perform I/O" is to perform an input or output operation.

I/O devices are the pieces of hardware used by a human (or other system) to communicate with a computer. For instance, a keyboardor computer mouse is an input device for a computer, while monitors and printers are output devices. Devices for communication between computers, such as modems and network cards, typically perform both input and output operations.

The designation of a device as either input or output depends on perspective. Mouse and keyboards take physical movements that the human user outputs and convert them into input signals that …

What is Removable media?

Removable media is any type of storage device that can be removed from a computer while the system is running. Examples of removable media include CDs, DVDs and Blu-Ray disks, as well as diskettes and USB drives. Removable media makes it easy for a user to move data from one computer to another.





In a storage context, the main advantage of removable disks is that they can deliver the fast data backup and recovery times associated with storage area networks (SANs) while also providing the portability of tape that may be required to meet corporate backup and recovery requirements. The main drawback of removable media is that it's more expensive than tape.

Hard Drive Technologies

hard disk drive (HDD), hard diskhard drive, or fixed disk, is an electromechanical data storage device that uses magnetic storage to store and retrieve digital information using one or more rigid rapidly rotating disks (platters) coated with magnetic material. The platters are paired with magnetic heads, usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is accessed in a random-access manner, meaning that individual blocks of data can be stored or retrieved in any order and not only sequentially. HDDs are a type of non-volatile storage, retaining stored data even when powered off.

Introduced by IBM in 1956, HDDs became the dominant secondary storage device for general-purpose computers by the early 1960s. Continuously improved, HDDs have maintained this position into the modern era of servers and personal computers. More than 200 companies have produced HDDs historically, though after extensive industry consolidation most units are ma…