File extension ZIP is used for ZIP compressed files. A ZIP sample file is provided. Free software for creating and opening ZIP files are listed.

File Extension: .ZIP

MIME Type: application/zip

File Content: Compressed files

What is ZIP? ZIP is a file format used to archiving files with data compression. ZIP was created by Phil Katz and released as an open format in 1989.

Some technical notes on ZIP file format:

• Each file is archived and compressed separately allowing faster single file retrieval.
• The most commonly used compression algorithm in ZIP files is the DEFLATE algorithm developed by Phil Katz.
• A large ZIP file can be divided into multiple volumes. This allows a single ZIP file to be stored on multiple floppy diskettes or other removable media.
• ZIP files can be protected by passwords.
• Files with non-ASCII character file names can be archived into ZIP files.

ZIP is the file extension for ZIP files.

ZIP files are binary files. Here are the first 64 bytes of a sample ZIP file dumped in HEX values:

50 4b 03 04 14 00 00 00 08 00 8f b8 24 38 9d aa PK...........8..
4a f1 6c 00 00 00 7e 00 00 00 0c 00 00 00 57 65 J.l...........We
6c 63 6f 6d 65 2e 6a 61 76 61 2b 28 4d ca c9 4c lcome.java..M..L
56 48 ce 49 2c 2e 56 08 4f cd 49 ce cf 4d 55 a8 VH.I..V.O.I..MU.

As you can see, "PK" is the magic number used to identify ZIP files. "PK" is actually the initials of Phil Katz, the creator of the ZIP format.

ZIP sample file: Click sample.zip to download.

ZIP files can be created and edited by many free compression software:

• SecureZIP - Creates and edits ZIP files, developed by PKWARE.
• FREE Unzip Utility for Windows - Opens ZIP files, developed by PKWARE.
• FreeZip - Creates and edits ZIP files.
• Info-ZIP - Creates and edits ZIP files. An open source software.