Introduction of Integrated circuit

Integrated circuits were made possible by investigational discoveries which showed that semiconductor devices could carry out the functions of vacuum tubes, and by mid-20th-century technology advancements in semiconductor device manufacture. The integration of large numbers of tiny transistors into a small chip was an enormous development over the manual assembly of circuits using discrete electronic components. The integrated circuit's mass production capability, reliability, and building-block approach to circuit design ensured the rapid adoption of standardized ICs in place of designs using discrete transistors. There are two main advantages of Integrated Circuits over discrete circuits: cost and performance. Cost is low because the chips, with all their mechanism, are printed as a unit by photolithography and not constructed a transistor at a time. Performance is high since the components switch quickly and consume little power, because the components are small and close together.

Digital circuits

Most integrated circuits of sufficient complexity utilize a clock signal in order to synchronize different parts of the circuit and to account for propagation delays. As ICs become more complex, the problem of supplying accurate and synchronized clocks to all the circuits becomes increasingly difficult. The preeminent example of such complex chips is the microprocessor, the central component of modern computers, which relies on a clock from a crystal oscillator.

A clock signal might also be gated, that is, joint with a controlling signal that enables or disables the clock signals for a certain part of a circuit. This technique is often used to save power by efficiently shutting down portions of a digital circuit when they are not in use.

In some near the beginning microprocessors such as the National Semiconductor IMP-16 family, a multi-phase clock was used. In the case of the IMP-16, the clock had four phases, each 90 degrees apart, in order to synchronize the operations of the processor core and its peripherals. Most modern microprocessors and microcontrollers use a single-phase clock, however.

Many modern microcomputers utilize a "clock multiplier" which multiplies a lower frequency external clock to the suitable clock rate of the microprocessor. This allows the CPU to operate at a much higher frequency than the rest of the computer, which affords performance gains in situations where the CPU does not need to wait on an external factor.

Web Design

Web design is the deceitful and graphical production of content shown on the Internet in the form of Web sites and other Web applications using many dissimilar forms of media. A Web site is a group of information regarding a particular topic or subject. Designing a website is defined as the arrangement and construction of Web pages that in turn make up a website.

There are several aspects in this process, and due to the rapid development of the Internet, new aspects may come out. For distinctive commercial Web sites, the basic aspects are:

* The site design is defined by the subject and content.
* The site should be user-friendly, with the interface and navigation simple and reliable. If the site is large enough and contains enough information, a site browser may be needed so that information can be found quickly, without using the navigation tools.
* The appearance should consist of a single style that flows throughout, to show consistency. The style should be professional, look good and most of all is appropriate to the users and site content.
* The visibility of the site's text and information should be dominant as that is what the users are visiting for.
* The site must also be easy to find on the internet and if possible should be scheduled on most, if not all, major search engines.

A Web site typically consists of text and images. The first page of a website is Home page or Index. Some websites use what is commonly called a Splash Page. Splash pages might include a welcome message, language/region selection, or disclaimer. Each web page contained by a Web site is an HTML file which has its own URL. After each Web page is created, they are typically associated together using a navigation menu composed of hyperlinks. Faster browsing speeds have led to shorter awareness spans and more demanding online visitors and this has resulted in less use of Splash Pages, particularly where commercial websites are concerned.

Once a Web site is completed, it must be published or uploaded in order to be viewable to the public over the internet. This is done using an FTP client. Once published, the Web master may use a variety of techniques to increase the traffic, or hits, that the website receives. This may include submitting the Web site to a search engine such as Google or Yahoo, exchanging links with other Web sites, creating affiliations with similar Web sites, etc.

Basket

A basket is a container which is usually constructed from stiff fibers, often made of willow. The top is either left open or the basket may be fitted with a lid.
Contents
1 chronological usage
2 contemporary usages
3 metaphorical and legendary usages
4 verandas of baskets
5 observe also
Historical usage
Wood, bamboo, wheat, other grasses, osiers or wicker are often used to make baskets, but they are also made today from plastic. The first baskets were natural fiber by gatherers to collect fruits, grains, nuts and other edible plant materials, as well as for holding fish by early fishing peoples. A creel is a basket made particularly to hold fish. The plant life available in a region affects the choice of material, which in turn influences the weaving technique. Rattan and other members of the Arecaceae or palm tree family, the thin grasses of temperate regions and broad-leaved tropical bromeliads each require a different method of twisting and braiding to be made into an effective basket. Although baskets were usually created to serve men in bed rather than an artistic purpose, the practice of basket making has evolved into an art.

History of glass

Naturally occurring glass, such as obsidian, has been used since the stone age. The first recognized instructions for glass making are in Egypt around 1500 BC, when glass was used as a varnish for ceramic and other items. In the first century BC the method of blowing glass was urbanized and what had once been an enormously rare and valuable item became much more common. During the Roman Empire many forms of glass were created, mostly for use in vases and bottles. Glass was made from sand, plant ash and lime. The initial use of glass was as a colored, opaque, or transparent glaze applied to ceramics before they were fired. Small pieces of colored glass were considered valuable and often rivaled valuable gems as jewelry items. As time passed, it was discovered that if glass is heated until it becomes semi-liquid, it can be shaped and left to cool in a new, solid, independently standing shape. In the first century BC, somewhere at the eastern end of the Mediterranean, a new invention caused a true revolution in the glass industry. This was the detection of glassblowing, both free-blowing and mold-blowing. The color of "natural glass" is green to bluish green. This color is caused by the unstable amounts of naturally occurring iron impurities in the sand. Common glass today usually has a slight green or blue tint, arising from these same impurities. Glassmakers educated to make colored glass by adding metallic compounds and mineral oxides to produce brilliant hues of red, green, and blue - the colors of gemstones. When gem cutters educated to cut glass, they found that clear glass was an excellent refractor of light, the fame of cut clear glass soared, that of colored glass diminished.