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The Mechanical Universe

Draw with your finger


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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 ...

Minispreadsheet Instructions
This is the instructions for Minispreadsheet. Minispreadsheet is a tiny extremely easy to use spreadsheet. You can type text or a number into a cell, that's it. You can also apply simple formulas to a cell. 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 ...

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 ...

IPv4 to IPv6 Transition With the Dual-Stack Technique
Transition from IPv4 to IPv6 has been slow. If you can't immediately convert all your network hardware to IPv6, the dual-stack technique allows the easiest operation of IPv4 and IPv6 devices on the same network. 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 ...

Fiber Optic Bend Radius Standards
Fiber optic cable can be damaged by placing too much tension on the cable or bending the cable excessively during installation. Excessive bending or too much pulling force can permanently damage the fiber by causing micro cracks. 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 ...

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 ...

A Brief Introduction to 3D Printing
Previously, the only ways to create 3D objects was casting and molding. 3D printing involves creating an object by laying down layer over layer of material, building the object from the bottom up. 3d printing is great for rapid prototyping. 3d printing is also a great way for a home artist to express their creativity. More ...

Understanding Modern PC Specifications
There is a huge variety of different PCs available out there. Its no wonder that consumers are confused about what to buy. This article explains modern PC specifications. More ...

The Evolution of Hard Disk Bit Recording
Hard drive technology has continuously improved over the decades, that includes higher storage capacity performance. Part of this improvement has been higher access speeds, but most of the higher storage capacity has been the result of changes in the bit recording methods. 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 ...

Access Useful Laptop Settings in the Windows Mobility Center
Some useful laptop settings are collected together in a group called the Windows Mobility Center. Near the top of the secret menu, select Mobility Center. Here you'll find controls for setting the screen brightness, sound volume, screen orientation, and such. More ...

Regular Expressions Intervals
Regular expression intervals tell us about the number of occurrences of a character in a string. Curly braces are used to define a precise count of how many occurrences you are checking for. 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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