Archive for the ‘history’ Category

[extracted from one of our preferred online feeds - HowToGeek.com]

Become a Vi Master by Learning These 30+ Key Bindings

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Vi is a powerful text editor included on most Linux systems. Many people swear by vi and find it faster than any other editor once they’ve learned its key bindings. You can even use vi key bindings in Bash.

We’ve already covered getting started with vi for beginners. If you haven’t used vi in a while, you might want to give that post a look to get a refresher on the basics.

Mode Switching

As a short recap, vi is a modal editor – there’s an insert mode and a standard command mode. In insert mode, vi functions similar to a normal text editor. In command mode, you take advantage of these key bindings.

  • i – Enter insert mode.
  • Escape – Leave insert mode. If you’re already in command mode, Escape does nothing, so you can press Escape to ensure you’re in command mode.

Moving the Cursor

Vi uses the hjkl keys to move the cursor in command mode. Early computer systems didn’t always have arrow keys, so these keys were used instead. One advantage of these keyboard shortcuts is that you don’t have to move your fingers from the home row to use them.

  • h – Move cursor left.
  • j – Move cursor down.
  • k – Move cursor left.
  • l – Move cursor right.

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:-) Let’s blow the 29 candles for the birth of the IBM Personal Computer known as “PC” !!

The IBM PC was announced to the world on 12 August 1981, helping drive a revolution in home and office computing. it was the original version and progenitor of the IBM PC compatible hardware platform.
The machine was developed by a team headed by Don Estridge in Boca Raton, Florida, at the IBM Entry Systems Division.

The cheapest version cost was about $1,500. Nowadays, that amount of money would represent $3500 !!
Do you imagine paying such amount for your home PC??

The phrase “Personal Computer” was common currency before 1981, and was used as early as 1972 to characterize Xerox PARC’s Alto. However, because of the success of the IBM PC, what had been a generic term came to mean specifically a microcomputer compatible with IBM’s specification.

The Intel 8088 is an Intel microprocessor based on the 8086, with 16-bit registers and an 8-bit external data bus. The processor was used in the original IBM PC.
The 8088 was targeted at economical systems by allowing the use of 8-bit designs. Large bus width circuit boards were still fairly expensive when it was released. The prefetch queue of the 8088 is 4 bytes, as opposed to the 8086′s 6 bytes. The descendants of the 8088 include the 80188, 80288, 80186, 80286, 80386, 80486, & 80388 microcontrollers which are still in use today. See the list below for a more complete list.
The most influential microcomputer to use the 8088 was, by far, the IBM PC. The original PC processor ran at a clock frequency of 4.77 MHz. A popular clone using an 8088 was the Leading Edge Model D, with a switch to select running at 4.77 MHz or 7.16 MHz.
Apparently IBM’s own engineers wanted to use the Motorola 68000, and it was used later in the forgotten IBM Instruments 9000 Laboratory Computer, but IBM already had rights to manufacture the 8086 family, in exchange for giving Intel the rights to its bubble memory designs. A factor for using the 8-bit Intel 8088 version was that it could use existing Intel 8085-type components, and allowed the computer to be based on a modified 8085 design. 68000 components were not widely available at the time, though it could use Motorola 6800 components to an extent. Intel bubble memory was on the market for a while, but Intel left the market due to fierce competition from Japanese corporations who could undercut by cost, and left the memory market to focus on processors.

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