Pixels are the basic element of all digital media. They are the smallest part of an image, video, or sound file, but they are very important because they help determine the resolution of the image and thus the size of the screen on which it is displayed. The size of the screen on which it is displayed. A web page without pixels is a white screen. Every image you see on the Internet, even if it's a GIF or JPEG, is made up of many small squares of color called pixels.
The size of a pixel is determined by the resolution of the image, video or sound file. That is, the larger the pixels, the higher the quality of the medium. A good example is that a 4K UHD TV has a much higher quality than a 720P HD TV.
There are three types of pixels:
Bitmap pixels - these are the pixels of an image, e.g. a photo or a scanned document.
Vector pixels - these are the pixels of a vector graphic. They are not rasterized like bitmap pixels.
Pixel grid - these are the pixels of a screen. The resolution of a screen is also called dots per inch (dpi). It refers to the number of dots in an inch on the screen. It is usually expressed in pixels per inch (ppi).
For a computer monitor, it is the number of dots on the screen per inch. The most common resolution for a computer monitor is 72 dpi.
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