Open ZIP File

Open ZIP File

ZIP file extension is used to store compressed files in ZIP file format. ZIP file format and DEFLATE compression algorithm was introduced by Phil Katz in PKWARE PKZIP compression/decompression utility. It was introduced as an alternative to ARC compression format and because it was released in public domain quickly gained popularity.

ZIP files utilize lossless compression. Most common compression method used by ZIP files is DEFLATE which is a combination of LZ77 algorithm and Huffman coding. ZIP file format is defined in RFC 1951.

ZIP file format supports password based symmetric encryption. It is not recommended to use that encryption since there are multiple flaws in it which can compromise archive security. Instead using AES encryption is recommended. AES encryption is available in ZIP file format documentation since version 5.2 and is supported by multiple ZIP applications including WinZip.

Older versions of ZIP file format supported only 4GB files and could have only 4GB maximum size of archive. With introduction of ZIP64 specification extension, ZIP can support of files and archives larger than 4GB. Most of the modern operating systems support compressing and decompressing files in ZIP64 format.

ZIP file format is currently adopted by all operating systems including Windows, Mac OS, Unix, Linux and others. Windows Explorer and Mac OS finder can open ZIP file and uncompress its content.

Open ZIP file on Windows

• Download WinZIP application from winzip.com and launch it by double-clicking on it.
• Launch WinZIP from the Start menu or Desktop. Click on File->Open archive in the WinZIP main menu.
• In the file open dialog select ZIP file you want to open and click "Open".
• You will see contents of the ZIP file and every file and folder stored in it.
• Select files and folders you want to extract and click on the "Extract to" icon.

ZIP files are transferred over e-mail or internet using following file multipurpose internet mail extensions (MIME) types: application/octet-stream, application/x-zip-compressed, multipart/x-zip.