ALZip

ALZip is an archive and compression utility software application from ESTsoft for Microsoft Windows that can unzip 40 different zip file archives. ALZip can zip files into eight different archive formats such as ZIP, EGG, TAR, and others. Introduced in ALZip version 8, the EGG archive format can be used, which supports Unicode and other features.

History
ALZip was developed in 1999 as an internal application by the South Korean software company ESTsoft in response to employee frustration with using the English interface in WinZip.

The Korean interface was immediately well received and later that year, ALZip was publicly released  as freeware. In just over a year, ALZip became the most popular zip program in Korea and by December 2001, was the top downloaded software in the country. By 2004, it had reached a 70% market share in South Korea. The popularity of the software and the ALZ archive format played a large role in earning ESTsoft a place in the Digital Innovation Awards Top 100 Companies in South Korea with the software taking special mention.

Early in its development, ALZip introduced the ALZ file format to deal with file size limitations of the ZIP file format. ALZ compression has no theoretical upper limit for file sizes, as they are only limited by operating system limits or the amount of available storage. The file format has become common in Korea.

The first English version was released in 2002. Since then, support for over 20 languages has been added.

Version 11.07 is available through Microsoft Store.

Licensing changes
ALZip was originally released as pure freeware. However in October 2001, it changed to free for home use, with government usage requiring a software license. In April 2002, a business license was also introduced for commercial usage. Licensing was based on the honor system, and there were no nag screens.

With the version 7 release, the license was changed from freeware to adware, displaying downloaded banner ads. Beginning on December 1, 2008, all new releases are shareware requiring a paid license except in its original Korean language, which requires no licensing fee.

With version 8.51 from 22 August 2012, ALZip changed the license so that it can be licensed freely. On the download page of ALZip is a serial number to copy and paste when you start the program, in order to have the license for the software free of charge.

Naming and mascots
The name "ALZip" was chosen as the "AL" part is a transliteration from the program's Korean name "aljip" (Hangul: 알집), literally EggZip. Other ALTools feature similar egghead cartoon characters as mascots for each program.

Additionally, ALZip integrates into the "New Folder" function of Windows Explorer, where new folders are created with the option of using custom icons and names.

File format controversy
In 2003, there was a controversy over ALZip's own compression file format ALZ when a developer of another Korean compression utility, "빵집," insisted that ALZip users were forced to use the ALZip archiver when decompressing ALZ files. He also insisted that ESTsoft does not offer decompression libraries, and that third-party archiver developers have had to use reverse engineering to develop their own algorithms.

EGG format and AZO Algorithm
EGG format is compress another algorithms in file extension.(ex: .txt -> Bzip2, .exe -> Deflate) if file extension is .com or .sys, ALZip compresses them in the AZO algorithm. The AZO algorithm is slow but has a very high compression ratio. Basically, it shows a much better compression rate than the Deflate algorithm used in the ZIP format, and even showed a compression rate comparable to or better than the LZMA algorithm of 7zip, which is known to have the strongest compression rate. You can experiment by changing the extension of the file to .com and compressing it in egg format.

As a result of reverse engineering, it seems to be using almost the same compression method as LZMA. It has been confirmed that LZ77 is used, and it seems to use Binary Range Coding as the backend.