Learn web design, computer maintenance, programming, computer architecture, computer networking, electronics, mathematics, art and graphic design.

The Mechanical Universe

Draw with your finger


Learn more at amazon.com

Processor Interrupts
An interrupt is a signal to the processor indicating an event has occurred that needs immediate attention. When an interrupt occurs, the processors normal path of execution is interrupted in order to run a routine to service the interrupt requester. More ...

EMI, RFI, EMC, EMS, What's the Difference?
EMI, RFI, EMC, and EMS all refer to different aspects of radio frequency interference which may cause elecronic devices to malfunction. Correcting these problems can be an art and a science. More ...

Gift Giving in the Workplace
One thing that can add to the stress of the holiday season is workplace gift giving. giving a gift to a supervisor or manager sets up a conflict of interest and an ethics problem. In my opinion, holiday gifts should be given only to children. More ...

Area of an Ellipse Calculator
It's easy to calculate the area of an ellipse because it's similar to calculating the area of a circle ecept instead of Pi times the radius squared, its Pi times the long axis times the short axis. More ...

Regular Expression Basics : How many Matches?
A Regular Expression (regex) is a sequence of characters that define a pattern that allows you to search, match, locate, replace, manipulate, and manage text. In this article you'll learn how to use regular expressions to count the number of matches. More ...

Fundamentals of Windows Security
Today, criminals are more sophisticated, and groups have formed with significant financial backing to support the wrong doings of these groups. This book is for system administrators, cybersecurity and technology professionals, solutions architects, or anyone interested in learning how to secure their Windows-based systems. More ...

Export Inkscape Drawing as an Image
Although Inkscape images can be embedded in webpages, for most other applications you'll need a raster image format. Inkscape can export your drawing in the .png raster image format. More ...

Regular Expressions Subexpressions
In this article you learned how to use subexpressions to rearrange matches in a regular expression and how to replace the value of a subexpression match in the results. More ...

Inkscpe Snap Controls Bar
some Inkscape users find snap annoying and so they disable it. Other Inkscape user's could not possibly work without snap. You can convert SVG to STL to print 3D models. But to do that you need accuracy that you cannot achieve without snap. More ...

Easy CSS Animated Flaming Text
I provide easy code to create CSS flaming text animations. You are free to experiment with your own CSS property values. I bet you can create even better flaming text. CSS3 flaming text animations are fun and easy to create. More ...

Easy JavaScript FileReader Code
The JavaScript FileReader object allows web pages to read files stored on the user's computer. Files may be selected using the input element, or selected with a drag and drop operation. More ...

Create a Cool Picture Frame Effect with CSS
By setting the CSS border-color property to a transparent color, and setting the background-origin property to border-box you can create a cool picture frame effect. More ...

Area of a Quadrilateral Calculator
If you have a regular quadrilateral there are simple formulas to calculate the area. But if you have an irregular quadrilateral you can calculate its area by viewing it as two triangles bucked up against one another. Find the area of each triangle, and then add them together. More ...

Windows Event Logs for Maintaining or Troubleshooting Your PC
Your PC keeps logs of everything that happens. You can use the information in these logs to help maintain and troubleshoot and your PC. More ...

Introduction to HTML
A Web server sends the response to the client browser with a set of instructions written in HTML (HyperText Markup Language). HTML consists of tags that define the structure of a web page. It is the standard markup language for documents to be displayed in a web browser. More ...

Regular Expressions Lookarounds
In this article you learn how to match a pattern only when it comes after another pattern (or after not that pattern) or only when it comes before another pattern (or before not that pattern). More ...


See it at amazon.com

Custom Search