Data compression. We use data compression to make files smaller. There are a few different compression techniques that can be used, and they fall into two categories. lossless compression means that only redundant data is removed was lossy data compression is where you remove information from a file that may reduce the quality of that file. One example of a lossless data compression technique is run length encoding. In this technique, the number of times a character or pixel is repeated in a row is given as well as the data Batman pixel or character.

In the example, we see that there are for each of the letter A t, H and B. Using one byte per character, this would mean that the file size would be 16 bytes. However, if we were to store the data as ma'am shown for a 44, h four We wouldn't have lost any of the data. But instead of 16 bytes if and only take eight bytes to store. This is an example of a compression technique. Thank you for watching this presentation.

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