Storage Capacity Measurement

1. Kilobyte (KB) - One thousand bytes

2. Megabyte (MB) - One million bytes

3. Gigabyte (GB) - One billion bytes

4. Terabyte (TB) - One trillion bytes 

5. Petabyte (PB) - One quadrillion bytes

HARDWARE - SECONDARY STORAGE - LOGICAL DATA ELEMENTS

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Secondary Storage

Secondary storage means external storage. This storage device includes a magnetic disk, optical disk, magnetic tape and others. The most widely used external storage is as follows:

Logical Data Elements

If there is no systematic way to store and retrieve data, it is too difficult to get any information from an information system. Therefore, data resource should be organized in some logical manner. Data are logically organized into characters, fields, records, files, and database.

Character: A character is the most elementary logical data element, whereas bit and byte are basic physical storage elements. A character consists of a single alphabetic letter, numeric digit, or special symbol. The character is equivalent to a byte.

Field: The next higher level of data is the field. A field consists of a grouping of related characters. For example, a set of characters in a customer's name makes a name field. A field represents an attribute of an entity.

Record: A record is a collection of related fields. The record represents a collection of attributes that describe an entity.

File: A set of related records makes a file. For example, a customer file consists of many records of customers.

Database: A database is an integrated collection of logically related files. A database combines several records previously stored in separated files.

Web Languages

1. HTML 

• a page description language that creates hypertext documents for the web.

2. XML

• describes web page content by applying identifying tags of contextual labels to the data.

3. Java

• Objected-oriented programming language that is simple, secure and platform independent.
• Java applets can be executed on any computer.

Steve Jobs Biography

Steve Jobs

 

QUICK FACTS

• NAME: Steve Jobs
• OCCUPATION: Entrepreneur, Computer Programmer, Inventor
• BIRTH DATE: February 24, 1955
• DEATH DATE: October 05, 2011
• EDUCATION: Reed College
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BEST KNOWN FOR

Steve Jobs co-founded Apple Computers with Stephen Wozniak. Under his guidance, the company pioneered a series of revolutionary technologies including the iPhone and iPad.

 

 

 

Synopsis

Steve Jobs was born February 24, 1955, to two University of Wisconsin graduate students who gave him up for adoption. Smart but directionless, Jobs experimented with different pursuits before starting Apple Computers with Stephen Wozniak in the Jobs' family garage. Apple's revolutionary products, which include the iPod, iPhone and iPad, are now seen as dictating the evolution of modern technology.

Early Life

Steven Paul Jobs was born on February 24, 1955, to Joanne Simpson and Abdulfattah "John" Jandali, two University of Wisconsin graduate students who gave their unnamed son up for adoption. His father, Abdulfattah Jandali, was a Syrian political science professor and his mother, Joanne Simpson, worked as a speech therapist. Shortly after Steve was placed for adoption, his biological parents married and had another child, Mona Simpson. It was not until Jobs was 27 that he was able to uncover information on his biological parents.

As an infant, Steven was adopted by Clara and Paul Jobs and named Steven Paul Jobs. Clara worked as an accountant and Paul was a Coast Guard veteran and machinist. The family lived in Mountain View within California's Silicon Valley. As a boy, Jobs and his father would work on electronics in the family garage. Paul would show his son how to take apart and reconstruct electronics, a hobby which instilled confidence, tenacity, and mechanical prowess in young Jobs.

While Jobs has always been an intelligent and innovative thinker, his youth was riddled with frustrations over formal schooling. In elementary school he was a prankster whose fourth grade teacher needed to bribe him to study. Jobs tested so well, however, that administrators wanted to skip him ahead to high school—a proposal his parents declined.

After he did enroll in high school, Jobs spent his free time at Hewlett-Packard. It was there that he befriended computer club guru Steve Wozniak. Wozniak was a brilliant computer engineer, and the two developed great respect for one another.

Apple Computers

After high school, Jobs enrolled at Reed College in Portland, Oregon. Lacking direction, he dropped out of college after six months and spent the next 18 months dropping in on creative classes. Jobs later recounted how one course in calligraphy developed his love of typography.

In 1974, Jobs took a position as a video game designer with Atari. Several months later he left Atari to find spiritual enlightenment in India, traveling the continent and experimenting with psychedelic drugs. In 1976, when Jobs was just 21, he and Wozniak started Apple Computers. The duo started in the Jobs family garage, and funded their entrepreneurial venture after Jobs sold his Volkswagen bus and Wozniak sold his beloved scientific calculator.

Jobs and Wozniak are credited with revolutionizing the computer industry by democratizing the technology and making the machines smaller, cheaper, intuitive, and accessible to everyday consumers. The two conceived a series of user-friendly personal computers that they initially marketed for $666.66 each. Their first model, the Apple I, earned them $774,000. Three years after the release of their second model, the Apple II, sales increased 700 percent to $139 million dollars. In 1980, Apple Computer became a publically traded company with a market value of $1.2 billion on the very first day of trading. Jobs looked to marketing expert John Scully of Pepsi-Cola to help fill the role of Apple's President.

Departure from Apple

However, the next several products from Apple suffered significant design flaws resulting in recalls and consumer disappointment. IBM suddenly surpassed Apple sales, and Apple had to compete with an IBM/PC dominated business world. In 1984 Apple released the Macintosh, marketing the computer as a piece of a counter culture lifestyle: romantic, youthful, creative. But despite positive sales and performance superior to IBM's PCs, the Macintosh was still not IBM compatible. Scully believed Jobs was hurting Apple, and executives began to phase him out.

In 1985, Jobs resigned as Apple's CEO to begin a new hardware and software company called NeXT, Inc. The following year Jobs purchased an animation company from George Lucas, which later became Pixar Animation Studios. Believing in Pixar's potential, Jobs initially invested $50 million of his own money into the company. Pixar Studios went on to produce wildly popular animation films such as Toy Story, Finding Nemo and The Incredibles. Pixar's films have netted $4 billion. The studio merged with Walt Disney in 2006, making Steve Jobs Disney's largest shareholder.

Reinventing Apple

Despite Pixar's success, NeXT, Inc. floundered in its attempts to sell its specialized operating system to mainstream America. Apple eventually bought the company in 1997 for $429 million. That same year, Jobs returned to his post as Apple's CEO.

Much like Steve Jobs instigated Apple's success in the 1970s, he is credited with revitalizing the company in the 1990s. With a new management team, altered stock options, and a self-imposed annual salary of $1 a year, Jobs put Apple back on track. His ingenious products such as the iMac, effective branding campaigns, and stylish designs caught the attention of consumers once again.

 Pancreatic Cancer

In 2003, Jobs discovered he had a neuroendocrine tumor, a rare but operable form of pancreatic cancer. Instead of immediately opting for surgery, Jobs chose to alter his pescovegetarian diet while weighing Eastern treatment options. For nine months Jobs postponed surgery, making Apple's board of directors nervous. Executives feared that shareholders would pull their stocks if word got out that their CEO was ill. But in the end, Job's confidentiality took precedence over shareholder disclosure. In 2004, he had a successful surgery to remove the pancreatic tumor. True to form, in subsequent years Jobs disclosed little about his health.

Recent Innovations

Apple introduced such revolutionary products as the Macbook Air, iPod, and iPhone, all of which have dictated the evolution of modern technology. Almost immediately after Apple releases a new product, competitors scramble to produce comparable technologies. In 2007, Apple's quarterly reports were the company's most impressive statistics to date. Stocks were worth a record-breaking $199.99 a share, and the company boasted a staggering $1.58 billion dollar profit, an $18 billion dollar surplus in the bank, and zero debt.

In 2008, iTunes became the second biggest music retailer in America-second only to Wal-Mart. Half of Apple's current revenue comes from iTunes and iPod sales, with 200 million iPods sold and six billion songs downloaded. For these reasons, Apple has been rated No. 1 in America's Most Admired Companies, and No. 1 amongst Fortune 500 companies for returns to shareholders.

Personal Life

Early in 2009, reports circulated about Jobs' weight loss, some predicting his health issues had returned, which included a liver transplant. Jobs had responded to these concerns by stating he was dealing with a hormone imbalance. After nearly a year out of the spotlight, Steve Jobs delivered a keynote address at an invite-only Apple event September 9, 2009.

In respect to his personal life, Steve Jobs remained a private man who rarely discloses information about his family. What is known is Jobs fathered a daughter with girlfriend Chrisann Brennan when he was 23. Jobs denied paternity of his daughter Lisa in court documents, claiming he was sterile. Jobs did not initiate a relationship with his daughter until she was 7 but, when she was a teenager, she came to live with her father.

In the early 1990s, Jobs met Laurene Powell at Stanford business school, where Powell was an MBA student. They married on March 18, 1991, and lived together in Palo Alto, California, with their three children.

Final Years

On October 5, 2011, Apple Inc. announced that co-founder Steve Jobs had died. He was 56 years old at the time of his death.

Moore's Law

Moore's law describes a long-term trend in the history of computing hardware: the number of transistors that can be placed inexpensively on an integrated circuit doubles approximately every two years. This trend has continued for more than half a century. 2005 sources expected it to continue until at least 2015 or 2020. However, the 2010 update to the International Technology Roadmap for Semiconductors has growth slowing at the end of 2013, after which time transistor counts and densities are to double only every 3 years.

The capabilities of many digital electronic devices are strongly linked to Moore's law: processing speed, memory capacity, sensors and even the number and size of pixels in digital cameras. All of these are improving at (roughly) exponential rates as well (see Other formulations and similar laws). This exponential improvement has dramatically enhanced the impact of digital electronics in nearly every segment of the world economy. Moore's law describes a driving force of technological and social change in the late 20th and early 21st centuries.

 The law is named after Intel co-founder Gordon E. Moore, who described the trend in his 1965 paper. The paper noted that the number of components in integrated circuits had doubled every year from the invention of the integrated circuit in 1958 until 1965 and predicted that the trend would continue "for at least ten years". His prediction has proved to be uncannily accurate, in part because the law is now used in the semiconductor industry to guide long-term planning and to set targets for research and development.

Computer Storage

• CD (compact disc) - the most common type of removable media, suitable for music and data.
  • CD-ROM Drive - a device used for reading data from a CD.
  • CD Writer - a device used for both reading and writing data to and from a CD.
• DVD (digital versatile disc) - a popular type of removable media that is the same dimensions as a CD but stores up to 12 times as much information. It is the most common way of transferring digital video, and is popular for data storage.
  • DVD-ROM Drive - a device used for reading data from a DVD.
  • DVD Writer - a device used for both reading and writing data to and from a DVD.
  • DVD-RAM Drive - a device used for rapid writing and reading of data from a special type of DVD.
• Blu-ray Disc - a high-density optical disc format for data and high-definition video. Can store 70 times as much information as a CD.
  • BD-ROM Drive - a device used for reading data from a Blu-ray disc.
  • BD Writer - a device used for both reading and writing data to and from a Blu-ray disc.
• HD DVD - a discontinued competitor to the Blu-ray format.
• Floppy disk - an outdated storage device consisting of a thin disk of a flexible magnetic storage medium. Floppies are used today mainly for loading device drivers not included with an operating system release (for example, RAID drivers).
• Iomega Zip drive - an outdated medium-capacity removable disk storage system, first introduced by Iomega in 1994.
• USB flash drive - a flash memory data storage device integrated with a USB interface, typically small, lightweight, removable, and rewritable. Capacities vary, from hundreds of megabytes (in the same range as CDs) to tens of gigabytes (surpassing, at great expense, Blu-ray discs).
• Tape drive - a device that reads and writes data on a magnetic tape, used for long term storage and backups.

 Secondary storage

Hardware that keeps data inside the computer for later use and remains persistent even when the computer has no power.

• Hard disk - for medium-term storage of data.
• Solid-state drive - a device similar to hard disk, but containing no moving parts and stores data in a digital format.
• RAID array controller - a device to manage several internal or external hard disks and optionally some peripherals in order to achieve performance or reliability improvement in what is called a RAID array.