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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 ...

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 ...

Minispreadsheet
Minispreadsheet is a tiny extremely easy to use spreadsheet, You can type text into a cell, you type a number into a cell. A formula is a simple list of cells with basic mathematical operators between them. If you change the number in a cell used in a formula in a different cell, the value in the cell with the formula will be updated. 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 ...

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 ...

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 ...

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 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 ...

Create Your Own Database Using Only Notepad : CDV
In this article you learn how to create a database using only a basic text editor along with any web browser. You won't believe how simple and powerful this method is. The database we design will have powerful features. 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 ...

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 ...

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

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 ...

The figure and figcaption Tags
The html figure element is a container for an image and optionally for a figcaption element that defines a caption for that image. 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 ...


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