File compression

When we save any sort of file, for example, an image, audio file, etc. it can take up a lot of storage on our hard drive (or, more likely, SSD).

To save space, we can use something called compression. This is when we take a large file and making it smaller, by removing some of the data from it.

Types of compression

Depending on whether the original file can be perfectly reconstructed from the compressed version or not, there are two types of compression:

• Lossy compression
• Lossless compression

Benefits of compression

Compressing a file makes it smaller: there are two main benefits to this:

• It takes up less storage space on our hard drive.
• If we’re sending/receiving it over the internet, it will take less time and bandwidth to transfer the file - that can sometimes save money, too!

Drawbacks of compression

• If we use lossy compression, the original file can’t be perfectly reconstructed from the compressed version - some data is lost. This can lead to a loss in quality, and if we compress it too much, it can look really bad.
• If we use lossless compression, the original file can be perfectly reconstructed, but often, it uses a lot of CPU power to compress and decompress the file, which can make it slow to work with (think if you’ve ever tried to extract a large zip / gzipped-tarball file - it can take a long time).