Colour Theory

The different wavelengths of electromagnetic radiation are what we see as different colours, as seen in the spectrum below.

Also, the colour wheel below, represents a spectrum shaped into a wheel which is useful for showing how colours related to eachother, the outcome of mixing colours, and the colours that are oppostie eachother represents colours that complement eachother.

Using too many colours on a website it worse than using too little. Too many makes it look too busy and makes it harder for the audience to find the information they are looking for, and tires the eyes quicker. A website with few colours however, has a risk of looking boring.

Analog Colors
The analog colors are those colors which lie on either side of any given color. Often these are color schemes found in nature. A site that makes use of analogous colors usually feels harmonious. The secondary color, as described above, can often be an analogous color.

Complementary Colors
The complementary colors are the colors which are directly opposite from one another on the color wheel. Complementary colors are contrasting and stand out against each other. Often it is a good idea to use a complementary color as the hightlight color, as described above.

Split Complementary Colors
Split complementary is a color and the analogous colors to its complement color. Using split complementary colors can give you a design with a high degree of contrast, yet still not as extreme as a real complementary color. It also results in greater harmony than the use of the direct complementary.

Triad Colors
Triad colors are three hues equidistant on the color wheel. When you want a design that is colorful and yet balanced, a triad color scheme might be the way to go.

Logo's

The first important factor when creating a logo is the inpact it creates first off, and if the audience immediately recognise it. It must also be easily copiable, in the sense that it still looks good if its in a leaflet or enlarged on a billboard. Another characteristic of an effective logo is if it portrays the company/organisation in a positive way, for example the 'Save the children' looks positive because it has a character reaching up in a cheerful manner. Also good logo's do not change regularly if they are effective as they are, if they did, people wouldn't be as familiar with the organisation.