How to Exit Vim

Simple help on exiting Vim.


5 Minute Vim Tutorial

This tutorial won't turn you into a Vim wizard, but at least you will be able to open, navigate, edit, and save files using Vim.


Understanding Supplementary and Complementary Angles

Supplementary and complementary angles are useful concepts to understand in trigonometry. Supplementary angles are any two angles that sum (add) up to 180° (a straight line). An easy way to remember this is that Supplementary and Straight line both begin with the letter ‘S’. Complementary angles are any two angles that sum (add) up to […]


Understanding the differences between various Linux distro's

There are many different operating systems (OS) out there. The most commonly known being Microsoft Windows and Mac OS, and then there is that OS called Linux that people keep talking about. It is not always clear what Linux is except that it is an operating system (sometimes claimed to be better than any other […]


Understanding the Law of Sines

While trigonometry is used to solve problems involving right angle triangles, it can also be applied to triangles that are not right angle triangles. Assumes you understand basic trigonometric concepts. A tutorial on understanding sine, cosine and tangent can be found here. A tutorial on understanding the trigonometric functions and the unit circle can be […]


Understanding Basic Trigonometric Identities

This tutorial assumes you are familiar with the trigonometric functions and their derivation from the unit circle. A tutorial on the trigonometric functions can be found here. A tutorial on the trigonometric functions and the unit circle can be found here. What is an Identity? An identity (in mathematics) is something that is true (more […]


Understanding Trigonometric Functions using the Unit Circle (Advanced)

While I call this advanced, it does not mean harder or more complicated, it just means more abstract. Understanding the trigonometric functions (sine, cosine, tangent) using right angle triangles is simply a special case of trigonometric functions using the unit circle. I strongly recommend first reading and understanding the article Understanding Sine, Cosine, and Tangent […]


Understanding Sine, Cosine and Tangent

An article explaining trigonometric functions using the unit circle can be found here Using the unit circle is the standard way trigonometric functions are defined and understood in mathematics. I recommend reading and understanding this article first. Later, if you want to understand how trigonometric functions are defined for values greater than 90° or less […]

Ubuntu 12.04

Basic Unity Interface / Desktop Tutorial

This is a basic tutorial for the Unity Interface / Desktop which comes with Ubuntu 12.04 – it should help get you up and running. There are differences between Unity shipped with Ubuntu 11.10 and Ubuntu 12.04. This tutorial reflects the way I understand and use the Unity interface. The Unity interface consists of four […]


Understanding Averages – Mean, Median, and Mode

This tutorial examines the concept of the average as a single value representing a collection of values. It focusses on the mean, median, and mode. The average (especially in physics) can also mean the center or balance point, but, for most everyday use, we tend to think of the average as representative value. Average comes […]


Keyword – switch, case, default

The switch keyword is probably the least well understood of the C/C++ language keywords (although, const probably comes a close second). The keywords switch, case, and default always go together and cannot be used independently in any other context. There is a small difference in behaviour between C and C++. Most programmers will never notice […]


Ubuntu 11.10 – Understanding sudo apt-get install …

This tutorial is for Ubuntu 11.10, however, it should be the same for other versions of Ubuntu (and derivatives, like edubuntu, kubuntu, lubuntu, and xubuntu) and other Linux distributions based on Debian. However, no guarantee is made. What makes Ubuntu very easy to use is the Ubuntu Software Center which allows users an easy way […]