Which type of data compression results in some data loss?

Lossy compression is a method of data compression that reduces file size by eliminating certain data, which ultimately results in some loss of quality or detail. This technique is commonly used for audio, images, and video where a perfect reproduction of the original file is not necessary for the end user, and where a significant reduction in file size is desirable.

In lossy compression, the algorithm analyzes the data and removes what it considers to be less significant information, often based on how the human senses perceive sound and visual content. For instance, in image files, subtle color variations that are not easily detectable to the human eye can be discarded. This allows for smaller files that occupy less storage space and can be transmitted more quickly, but at the cost of some fidelity to the original content.

Conversely, lossless compression retains all original data, ensuring that the file can be accurately reconstructed without any loss in quality. This approach is essential for applications where every bit of data matters, such as in many text files or certain image formats. Redundant compression is not a standard term in data compression, and data encryption serves a different purpose altogether by securing the data rather than compressing it.