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The Mechanical Universe

Draw with your finger


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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 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 ...

Online Color Coded Resistor Calculator
To determine the resistance value of a color-coded resistor, select the colors matching each band from the drop-down lists. More ...

Easy CSS 3D Mouse-over Pressed Text Effect
I provide easy CSS code for 3d text when you move your mouse pointer over the 3D text shown above, the text will appear to be pressed. In this example, I configured the 3d text in a link. 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 ...

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

Inkscape Basic Fill
In Inkscape you can fill a shape with just about any color, texture, or pattern that you desire. In this article we discuss how to fill a shape with a basic color. More ...

A Handful of Useful Run Commands: calc, notepad, wordpad, voice recorder, control
The Run dialog box which can be opened by pressing the [Windows] + [R] keys. Run dialog box is a rapid way to open programs. Here are some quick and useful Run commands. More ...

Introduction to Operating Systems
An operating system is software that acts as an intermediary between a computer user and the computer's applications and hardware. An operating system can be viewed as a resource allocator. Resources might be CPU time, memory space, file storage space, and input/output (I/O) devices. More ...

Inkscape Text Kerning
Although Inkscape might be considered a vector drawing application, it is also a powerful typographical design program. Actually Text Kerning is not a good title for this article because in it I will cover all the different typographical adjustments you can make in Inkscape. More ...

How to Draw an Airplane
Drawing an airplane is much easier if you first construct two-point perspective guidelines. This article shows you how to draw an airplane in ten easy steps. 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 ...

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 ...

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 ...

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 ...


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