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Showing posts with the label Computer

What is NTSC and PAL ?

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 Most countries in North and South America, including the US and Canada, utilize the National Television Standards Committee (NTSC) format, while Europe, Australia and parts of Asia use a competing format called Phase Alternating Line (PAL). The major distinction between these two formats is the rate at which a broadcast is displayed on a TV screen: NTSC displays at 30 frames per second (fps), while PAL provides 25 fps. Each format also uses a different number of lines on an old analog TV display when showing the signal, creating two different resolutions. The widespread adoption of High-Definition Televisions (HDTVs) by many consumers has not eliminated this difference, however, since older broadcasting methods have influenced digital signal playback. Primary Difference The differences between these formats really start with the electrical power system behind the transmissions viewed on a TV. In the US and countries like Canada and Mexico, electric...

What is DDR Memory?

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Double data rate synchronous dynamic random access memory, or DDR SDRAM for short, is a type of computer memory used in Pentium III or higher computers. DDR RAM is the computer’s primary working memory, storing program instructions and data for use by the central processing unit (CPU) through the bus controller. DDR memory belongs to the dual in-line memory module (DIMM) architectural family and is a faster form of SDRAM. Each module of DDR memory has one notch on the connecting side and two notches on the side that attach to latches on the PC motherboard to hold it in place. DDR RAM can come in either single-sided or double-sided chip configurations. Desktop DDR has 184 pins, as compared to 168 pins on SDRAM. Laptop versions, called SO-DIMMs, contain 200 pins.                                  ...

How do Scanners work?

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So it's 11:45 p.m. and you're laying alone on your dust ridden bed watching fancy television series (GoT, maybe) and suddenly your phone lines up with a message from a friend who reminds you of a deadline to submit a copy of a very important document, to the administration, that is sitting in your closet dust covered. So you're going to take a picture of it with your phone but you realize your crappy built-in phone camera and the poor lighting from the dingy bare bulb hanging from the ceiling just aren't helping. So decisively you dash to your PC and use your flatbed scanner and as you sit there listening to the whirling of the scanning mechanism and pondering how your life got to this point you find yourself asking how the heck do these things work anyway. Great question, your typical scanner uses something called a charge-coupled device or CCD to determine what's on the page. The main idea here being that the CCD can convert light into an electrical cha...

What is BIOS?

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A Basic Input/Output System (BIOS) is an electronic set of instructions that a Personal Computer (PC) uses to successfully start up. It is located on a chip on the motherboard inside of a computer and is designed to be protected from disk failure. While it can be updated, this should be done carefully to avoid damaging the computer or leaving it unable to start up. The Function of BIOS One of the main functions of the BIOS is to give instructions for the Power-On Self Test (POST). This self test ensures that the computer has all of the necessary parts and functionality needed to successfully start itself, such as use of memory and a keyboard and other components. If errors are detected during the test, the computer gives a code that reveals the problem. Error codes are typically presented as a series of beeps heard shortly after startup. The BIOS also works to give the computer basic information about how to interact with some critical components, such as hard dri...

USB Connectors : Type A vs Type B vs Type C

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Most computer users are familiar with Universal Serial Bus (USB), which has become the most commonly used way to connect peripheral devices to a computer. Your mouse, printer, digital camera, scanner, and other devices probably all connect to your computer via a USB port. Many memory storage devices, such as portable hard drives, flash drives, and memory card readers, also connect to a computer via USB. USB connectors make it possible to connect a device to your computer using USB. A long cable is used to connect the device to your computer. Usually, the connectors on each end of the cable are quite different, making it necessary to know which of them goes to your computer and which gets plugged into the device. The standard USB connector you’re most familiar with is USB Type-A. Even as we’ve moved from USB 1 to USB 2 and on to modern USB 3 devices, that connector has stayed the same. It’s as massive as ever, and it only plugs in one way (which is obviously nev...

What is a Hotspot?

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A hotspot is any public area where computers that have been fitted with wireless network technology can gain access to the Internet. The computer accomplishes this by contacting a nearby wireless network with its internal NIC (Network Interface Card). The NIC seeks out the radio waves generated by wireless networks. When it detects a signal strong enough, it asks permission to log on to the network. Though this access is often free, other times the wireless network requires registration and a small fee before it will grant the computer access. Many cafés now feature a wireless network environment or hotspot, so that customers can sit leisurely, sip coffee and work on their laptops with full Internet access. Establishments that offer hotspots are referred to as being wired , somewhat of a misnomer since the technology is wireless. Ad A network that generates a hotspot basically consists of a wireless router and modem. The RF, or radio frequency, waves used by a w...