Archive for category Lessons
📅 August 18, 2017
📅 July 31, 2017
“An object? What’s that?”
📅 July 24, 2017
Scripts are intended to be lightweight and short in order to consume fewer system resources than full-fledged applications. This way, pages render faster in a web browser.
No matter how simple or fancy a script might be, we need to plan before writing any code.
📅 July 19, 2017
📅 July 14, 2017
📅 July 13, 2017
📅 March 4, 2015
The word parity originates from the Latin word par, meaning equal. Take the sport of golf, for example. A hole on a golf course is usually assigned a par number. If you sink the golf ball into the hole with the same number of strokes as the par, you are said to be on par — equal to the number of expected strokes. If you expend more strokes than the par, then you need practice, and you should probably try again.
An identical strategy applies to computers. Parity is an early form of error detection often used with serial communications, such as modems and serial ports, for example. An extra bit is appended to each data byte to make the total number of 1 bits even or odd. This extra bit, called the parity bit, is separate from the data byte, and it does not contain data information. It is only used to make the total number of 1 bits even or odd.
There are two main types of parity: Even parity and odd parity. Both operate in the same manner aside from the evenness or oddness.
This lesson focuses on 8-bit data even though the concept can apply to any number of data bits, such as 7-bit ASCII.