A: Hexadecimal notation is the most common method for designating color on a web site. A hexadecimal color code is a six digit number with a # (hash) symbol in front of the value. Computers use units of two to count, rather than base 10. Hex is base 16 or 2 to the power of 4.

In the six digit value, the first two numbers define red, the next two define green and the last two define blue. Each digit has 16 values, using numbers and letters 0-9 and A-F. A through F function as the numbers 11 through 16. Because each color is represented by a pair of base 16 numbers, there are 256 (16 x 16) possible values for each color. When you combine the values of the three colors there is a possibility of 16,777,216 (256 x 256 x 256) combinations of color.

For example, pure red is #FF0000, pure green is #00FF00 and pure blue is #0000FF.

At first it may seem difficult to determine what color you will get with different color codes. A simple solution to this is to remember that FF is the maximum and 00 is the minimum, and use one of the following codes for each component:

FF means full brightness
CC means 80 percent brightness
99 means 60 percent brightness
66 means 40 percent brightness
33 means 20 percent brightness
00 means none of this color component

Sometimes you will find hexadecimal numbers expressed using only three digits, such as #F32. This is an abbreviation for a color that has a pair for each of the three numbers. #F32 is the same as #FF3322.

You will also see web pages that use color names to describe a color that is being used. The W3C’s HTML 4.0 specifies only 16 standard color names: aqua, black, blue, fuchsia, gray, green, lime, maroon, navy, olive, purple, red, silver, teal, white, and yellow. Most browsers today support more color names, but when specifying a color it is usually best to use a hexadecimal number as hexadecimal colors are supported by all browsers.

You should be aware that when viewing colors on a computer monitor, different monitors may display colors in very different tints. Neutral, earth-tone colors such as medium gray, tan and ivory can lead to even more unpredictable results on many computer monitors, and may even seem to change color on one monitor depending on the lighting conditions in the room and the time of day.

A: There are generally two problems you may encounter when you look for clipart or photos online. The first problem is finding something that you can legally use. If you do not know that you have the permission to use a piece of art, then you probably do not. You can use work that you have purchased the right to or have been given the right to use. You cannot use your favorite cartoon character or a professional photograph of your favorite singer.

The rule of thumb in looking for graphics online is to look for royalty-free clipart and photos. This means you may use the work without paying a continuing royalty fee for use. You may receive the right to use the artwork free of charge, you may pay a fee to access such artwork (say $15.95 a month for unlimited downloads), you may pay for the right to use that particular piece, or you may agree to link back to the creator’s site in exchange for the royalty-free use of the artwork.

The second problem with finding clipart and photos online is that good royalty-free art may be more expensive than you would hope. This is changing rapidly as sites like StockXchange, iStockPhoto and Dreamstime make it easier for photographers to sell their work and for consumers to find clipart they need.

The key to finding exactly the right art for your project is to have a very good idea of what you are going to need before you start. Think about color, shape, size and resolution (whether it will be printed or posted online makes a difference).

Decide what you need, find something that fits the bill, and move on with the rest of your project. Otherwise you may spend a waste a lot of time searching for something that may not exist. The biggest obstacle to finishing a project on-time and on-budget is trying to go from great to perfect, when great is usually good enough.