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The Mechanical Universe

Draw with your finger


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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 ...

Inkscape Layers and Z-Order
Inkscape's use of the Z axis is represented by layers and is called z-order. When you first draw an object on an empty canvas, it has a z-order of 1. If you draw a second object, it has a z-order of 2. If you draw a third object, it has a z-order of 3 and so on. 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 ...

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 ...

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 ...

Inkscape Exercise: Draw Photorealistic Sphere
Although Inkscape is a 2D drawing application, it is quite capable of drawing photorealistic 3D images. To demonstrate this capability, in this article I show you, step-by-step how to draw a photorealistic sphere. More ...

IPv6 Address Compressor Expander
Enter the IPv6 address in the top text box. Click on the appropriate button: Omit Leading Zeros, Consolidate Zeros Segments, Expand Zeros Segments, Replace Leading Zeros. The formatted address will appear in the bottom text box. More ...

How SSL (Secure Sockets Layer) Works
SSL is a security protocol standard that encrypts communication between a web browser and a web server. Any organization that uses their website to transmit, receive, store, or display confidential or sensitive information such as passwords, credit card or bank account numbers, social security numbers, and so on, needs to use an SSL Connection. 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 ...

PowerShell Script to Show Last 5 Errors in Event Log
The Windows System eventlog is one of the most powerful components of the operating system because it keeps a log of everything that happens. Here I provide a powershell script to display the last 5 error entries in the log. 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 ...

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 ...

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 ...

Regular Expression Basics : Match a Set of Characters
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 match a set of of characters. More ...

Inkscape Shadows and Highlights
Adding shadows and highlights to your drawings can create a touch of realism. In this article you learn how to add shadows and highlights to your Inkscape drawings. More ...

How to Check Your PCs TPM
One of the requirements for Windows 11 is TPM version 2.0. If you have Windows 10 and you have TPM version 2.0 module, and it's enabled, then you can install and run Windows 11. More ...


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