Network Interface Card (NIC)
A Network Interface Card (NIC) is an expansion card that allows a PC to connect to a network. Though there are many different types of networks, PCs almost always use a NIC that interfaces to a wireless network or an Ethernet network. More ...
What is Bluetooth?
Bluetooth is a wireless technology designed for short range data communications Two or more Bluetooth devices establish a connection and form a small network known as a Piconet. More ...
Serial ATA Hard Drive
New computers will begin using the SATA (Serial ATA) interface to the hard disk. Some new motherboards come with built-in SATA support. The SATA interface does not use a ribbon cable. Instead, it uses a cable similar to a network cable with only seven wires. More ...
Anatomy of a Liquid Crystal Display (LCD)
Color LCD displays have a sandwich-like structure. One layer of the sandwich has liquid crystal between two glass plates. One glass plate has a matrix of thin film transistors on it. Liquid crystals move depending upon the charge applied to a tiny capacitor by its related transistor. More ...
Intermediate PC Build-it-Yourself Guide
Before you get out your tool kit and put your anti-static mat on the floor, you have to consider a few factors before embarking on your computer-building odyssey? Now don't panic - it's not as complicated as it seems. More ...
History of the QWERTY Keyboard
In the late 1860s, American inventor Christopher Scholes developed the first typewriter. The keys were originally laid out in alphabetical order, but this led to problems with the type bars jamming when typing at speed. To remedy this, Scholes relocated the keys to keep the most frequently used letters apart, resulting in the QWERTY keyboard. More ...
PC Disk File Systems
The first PC file system, called FAT because it used a File Allocation Table, was developed in the early 1980?s for floppy disks. The File Allocation Table, a map of the location of files on the disk, is located near the beginning of the disk. More ...
Understanding PC Data Buses
Physically, a data bus is the connection between the CPU and other devices on the PCs motherboard. A data connection can be serial or parallel. The data bus used in first-generation PCs used 8-bit architecture. PCI Express uses switched serial connections. More ...
External Serial Advanced Technology Attachment (eSATA)
Initially all SATA (and PATA) interfaces were for internal hard disks. With the introduction of eSATA, the SATA interface can be used with external storage media. This puts eSATA in competition with Universal Serial Bus (USB) and Firewire. Especially since, like USB and Firewire, eSATA allows hot swapping. More ...
CompTIA A+ Training Kit - Safety Issues
When working on computers it's important to pay attention to safety considerations. CompTIA A+ Training Kit teaches computer safety issues as required for CompTIA A+ certification. More ...
The RS-232 Serial Port
The RS-232 serial port was used to connect a mouse, modem, and/or printer. The RS-232 serial port is now totally obsolete. I would be very surprised if you ever run into a PC with an RS-232 serial port except possibly in a third-world country. However, I'll briefly describe the it in this article because you may run into a question about it in the CompTIA A+ Certification Exam. More ...
Hardware Resources Explained
Hardware devices, such as modems, network circuits, sound circuits, and so on, require system resources such as Interrupt Request (IRQ) lines, Input/Output Port (I/O) addresses, Direct Memory Access Channels (DMA), and a range of Memory Addresses for storing code and data. Each device needs its own set of resources. If two devices attempt to use the same resource, your system may lock up or crash. More ...
Wireless USB
USB requires peripherals to be connected to the PC with cables. Some PC users feel they can be more productive if they could get rid of those cables. This has resulted in the introduction of several short range wireless connection technologies. More ...
PC Sound Circuitry
Actual physical sound is an analog phenomenon while the computer is digital. To output a sound stored on a computer disk to a speaker the sound circuit uses a digital-to-analog converter. Sound input to the computer for recording uses an analog-to-digital converter. So PC sound circuitry is primarily an AD/DA-converter or a "coder/decoder", usually shortened to "codec". More ...
