ASCII, Unicode, and Code Pages

ASCII, Unicode, and code pages are all ways of mapping the binary codes that computers use to store characters to a the characters on whichever keyboard you happen to be using and b what you see on-screen.

ASCII and Unicode are both standard character-encoding schemes for text-based data. If you have information that can be represented in characters such as this paragraph, for example, you can encode it in ASCII or in Unicode so that a computer can store it.

In ASCII, each character is represented by one byte. There are two forms of ASCII:

Standard ASCII uses a 7-bit binary number combination to represent each character, which gives enough combinations for 128 characters. Extended ASCII, which is also known as high ASCII, uses an 8-bit number combination for each character, which gives enough combinations for 256 characters. Given that the English alphabet uses 26 uppercase letters, 26 lowercase letters, 10 numbers, some punctuation  comma,  period,  parentheses,  and  so  on,  and  control  characters,  standard  ASCII’s capacity for 128 characters starts to look paltry. Extended ASCII doubles the ante and adds some foreign characters for example, accented characters, graphic symbols, and symbol characters to standard ASCII’s set.

Extended ASCII works pretty well provided you’re satisfied with 256 characters. But even 256 characters are far too few if you want anything beyond the main European languages.

The solution to the limitations of ASCII is Unicode. In Unicode, each character is represented by two bytes 16 bits, which gives 65,536 character combinations 256  256 - enough to cover most of the characters in the world’s many languages. As of the year 2000, about 39,000 of those 65,536 combinations had been assigned, with Chinese alone accounting for about 21,000 of them. Japanese, with its borrowed and mutated kanji, is another of the greedier languages for Unicode combinations. When do you have to worry about ASCII and Unicode? Windows Vista is pretty smart about Unicode, so usually you don’t have to worry about whether you’re using Unicode or ASCII, because Windows uses Unicode almost exclusively. For programs that don’t support Unicode, you can use code pages to enable the programs to communicate effectively with the user. A code page is a table that maps a program’s character codes which are binary to the keys on the keyboard, the characters on the display, or preferably both. Previous versions of Windows used code pages.

If you need to use a program that can’t handle Unicode, assign a code page for it as follows:

1.   Choose Start   Control Panel. Windows displays Control Panel.

2.   In the Clock, Language, and Region category, click the Change Keyboards or Other Input Method link. If you’re using Classic view, double-click the Regional and Language icon. Windows displays the Regional and Language Options dialog box.

3.   Click the Administrative tab. Windows displays the Administrative page.

4.   Click the Change Settings button. Windows displays the Regional and Language Settings dialog box.

5.   In the Select a Language for Non-Unicode Programs drop-down list, select the language to use.

6.   Click the OK button to close the Regional and Language Settings dialog box.

7.   If you want to copy these settings you’re applying to the system accounts or the default user account which controls any new user accounts that you or other Computer Administrator users create on this computer, click the Reserved Account Settings button. Windows displays another Regional and Language Settings dialog box.

8.   Select the Default User Account check box if you want to apply the changes to the default user account.

9.   Select the System Accounts check box if you want to apply the changes to the system accounts.

10. Click the OK button to close the Regional and Language Settings dialog box.

11. Click the OK button to close the Regional and Language Options dialog box. Here’s an example of inserting a Japanese kanji using Advanced view:

1.  In the Character Set drop-down list, select the Windows:

Japanese item.

2.  In the Group By drop-down list, select the grouping you want. In the example, this is Japanese Kanji by Hiragana. Character Map opens a window displaying the kanji.

3.  In the Japanese Kanji by Hiragana window, select the hiragana phonetic character that represents the sound of the kanji character. The main Character Map window with the Japanese Kanji by Hiragana window displays a scrolling list of kanji that can be pronounced with that sound.

4.  Select and copy the character as usual, then paste it into the document. If you need to enter a particular character frequently in your documents and don’t want to have to access Character Map each time, select the character in Character Map and memorize the Alt code displayed in the status bar. Only some characters have these Alt codes. To enter the character at the insertion point in a document, make sure that Num Lock is on, then hold down the Alt key and type the code for the character.

Using Private Character Editor to Create Your Own Characters

Windows includes a hidden applet called Private Character Editor that you can use for creating your own characters and logos. To run Private Character Editor, choose Start   Run or press Windows Key+R. Windows displays the Run dialog box. Enter eudcedit in the Open text box and click the OK button.

Paint

Paint Start   All Programs   Accessories   Paint is a basic illustration program that’s been included with almost all known desktop versions of Windows. Windows Vista’s version of Paint lets you create bitmap files BMP, DIB, GIF files, JPEG files JPG and JPEG, Por- table Network Graphic files PNG, and TIFF files TIF - enough to make it useful for basic illustration needs, and significantly better than the versions of Paint in most versions of Windows 9x, which could work only with bitmaps. If you’re into creating drawings or paintings on the computer, you’ll find that Paint’s limitations present more challenges than its capabilities do. Paint’s Image menu provides tools for flipping and rotating images, stretching and skewing images, changing their attributes for example, changing a color file to black and white, and inverting colors - but that’s about it. If you want to do serious image-editing work, consider a heavy-duty image-editing program such as Paint Shop Pro or Adobe Photoshop. If you want to do serious illustration work, investigate programs such as Adobe Illustrator, Procreate Painter, or CorelDRAW. If you’re not into creating drawings or paintings on the computer, you’ll probably find Paint quite useful for some basic graphical tasks such as the following:

Creating background images for your Desktop    If you want to use a digital photo or a scan as a background image for your Desktop, you may need to rotate it from a portrait orientation to a landscape orientation or crop it down to size. Capturing images directly from a web camera    You can capture images directly from a web camera by using the File   From Scanner or Camera command.

Cleaning up scanned images Images you scan can easily pick up dots from specks of dirt on the scanner or from damage to the picture. You can use Paint to edit pictures and remove small defects such as these.

Capturing screens If you’re preparing documentation on how to use software, you may want to capture the screen or a window. To capture the whole screen to the Clipboard, press the Print- Screen PrtScn key. To capture only the active window to the Clipboard, press Alt+PrintScreen. These keystrokes are from Windows itself rather than from Paint, so you don’t need to have Paint running while you issue them. Then activate Paint and choose Edit Paste to paste in the screen or window, where you can work with it as you would any other graphic.

Calculator

Though useful, Calculator Start   All Programs   Accessories   Calculator seems such a basic program that it barely deserves mention. But there are several things you should know about it:

•    Calculator displays itself by default in its Standard view, but it also has a Scientific view that’s useful if you need to work in hexadecimal, binary, or octal; calculate degrees or radians; or perform similar tasks. To switch Calculator to Scientific view, choose View   Scientific. To switch Calculator back to Standard view, choose View   Standard.

•    When you switch Calculator from Standard view to Scientific view, or switch it back, it wipes the display. To take the current number from one view to the other view, use the MS button to store it, switch view, and then use the MR button to retrieve it. Binary, octal, or hex numbers get converted to decimal when you move them to Standard view by using this technique.

•    You can operate Calculator entirely from the keyboard if you want to. Choose Help   Help Topics to open the Help file, then investigate the “Using Keyboard Equivalents of Calculator Functions” topic.

•    If you’re working with long numbers, you may want to choose View Digit Grouping to have Calculator group the digits into threes separated by commas. For example, with digit grouping, 44444444444 appears as 44,444,444,444, making it easier to read.

•    Press Esc to clear the Calculator.