Pixels and measuring images on your screen
What is a pixel?
A pixel is the smallest unit of programmable colour on a computer screen. On your screen this will appear as one tiny dot of colour. The physical size of a singular pixel depends on the resolution of your screen. This is all relative - a pixel will appear larger, the lower the resolution and smaller your screen.
We can use pixels to measure the width and height of images and even web pages. This is a much more useful measurement system than using centimeters or inches, as pixels are a standardised measurement which will maintain the correct proportions across any screen. Centimeters, however, can look vastly different between two different computers, dependent on monitor size and resolution.
There are many useful tools you can use to find out the pixel width of something on your screen. For example, if you are using Mozilla Firefox, you can download an add on tool called MeasureIt from here which will allow you to measure anything on your screen in pixels.
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