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The Mechanical Universe

Draw with your finger


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SVG Basic Shapes Tutorials
This is an introduction to SVG (Scalable Vector Graphics) and tutorials with examples on how to use simple code to draw basic shapes. 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 ...

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 ...

Regular Expressions Boundaries
In this article you learn how to controls where a regular expression matches a string, on a word or non-word boundary, at the beginning or end of a string. You also learned about multiline mode. More ...

Regular Expression Position Matching
In this article you how to use regular expressions to match characters at the beginning, end, both beginning and end, or at any specified location in a string. More ...

What is an Ethernet Crossover Cable?
When connecting two computers together without a switch or router in between you need a special cable, called a crossover cable, that has the transmit wire pair swapped with the receive wire pair. More ...

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 ...

Introduction to Windows PowerShell
PowerShell is a more powerful replacement for the command shell. this article explains how to run PowerShell and how to create and run PowerShell scripts. More ...

Inkscape Preferences
Inkscape is a highly configurable application. Many of these configuration options can be set through the Preferences dialog box. There is probably a hundred things you can configure through the Preferences dialog box. Here I'll describe a couple of the most important ones. More ...

HTML5 Header Element
The header element is one of HTML5's semantic elements. It provides a container for header information. A header element may contain ,logo author, navigation, search, version, copyright, and other such information. 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 ...

Regular Expression: Alternation
In this article you learn how to create an alternation regular expression that will match alternate patterns in a string. 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 ...

Fundamental Digital Logic Gates
All the advanced features of the most powerful computers, such as mulicore and parallel processing are done with digital logic. In this article I explain the fundamental concept of digital logic in simple and clear language so that anyone can understand it. More ...


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