In this article about the best developers, we will talk about the ZIP compression format, which has the virtue of compressing data without any loss. This simple computer invention revolutionized the exchange of digital data. We will highlight its history, the compression algorithm, its technical information, and the ZIP format today.
The lossless compression algorithm
The lossless compression algorithm used by ZIP to compress documents, images, or applications works on each file separately, allowing each file to be recovered independently without having to read the rest, which increases performance.
ZIP supports a symmetric encryption system, a cryptographic method that uses the same key to encrypt and decrypt messages. However, from a cryptographic standpoint, this system is quite weak against external attacks, such as plaintext, dictionary, and brute-force attacks.
The history of ZIP
In 1989, Phil Katz, the founder of PKWARE (the company that marketed PKZIP), invented and launched the ZIP format. Katz was inspired by ARC and improved the C compression routines, making the tool much faster compared with other data compression formats.
The ZIP format today
Today, ZIP files use the .zip extension and can contain one or more files. More importantly, other compression applications besides PKZIP use this format, including WinZip, WinRAR, PeaZip, and 7-Zip.
As for operating systems, Windows includes by default a plugin named zipfldr.dll. Mac OS X systems include built-in ZIP support in Finder, which is responsible for the total management of user files, disks, network, and launching other applications. Thus, ZIP is the official compression system for Mac OS X.
The ZIP format, being a pioneer in file compression, has inspired other companies and is the basis for Java's Jar format, used to distribute .class files. Compressed XML files in ZIP are also used by OpenDocument, OpenOffice, and OpenXML for Microsoft Office 2007.
Indeed, the ZIP format was a pioneer in data compression, and since its release it has inspired other lossless compression formats such as RAR and other derivative formats. We hope that whenever you compress a file with any free or commercial application, you'll know a bit more about its history and the technology it uses.
