QuickTime Alternative is a codec

Codec

A codec is a device or computer program capable of encoding or decoding a digital data stream or signal. The word codec is a portmanteau of "compressor-decompressor" or, more commonly, "coder-decoder"...

 package for Microsoft Windows

Microsoft Windows

Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...

 for playing QuickTime

QuickTime

QuickTime is an extensible proprietary multimedia framework developed by Apple Inc., capable of handling various formats of digital video, picture, sound, panoramic images, and interactivity. The classic version of QuickTime is available for Windows XP and later, as well as Mac OS X Leopard and...

 media, normally only playable by the official QuickTime software distribution from Apple Inc.

Comparison

QuickTime Alternative consists of codec libraries extracted from the official distribution, including the official QuickTime plugin required for playing QuickTime files (.MOV, .QT and others) in web browsers such as Internet Explorer

Internet Explorer

Windows Internet Explorer is a series of graphical web browsers developed by Microsoft and included as part of the Microsoft Windows line of operating systems, starting in 1995. It was first released as part of the add-on package Plus! for Windows 95 that year...

 and Mozilla Firefox

Mozilla Firefox

Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...

, and also includes Media Player Classic

Media Player Classic

Media Player Classic is a compact media player for 32-bit and 64-bit Microsoft Windows. The application mimics the look and feel of the old, lightweight Windows Media Player 6.4 but integrates most options and features found in modern media players...

.

The main functional differences between the official QuickTime distribution and QuickTime Alternative from an end-user standpoint are in feature set, size, and consumption of system resources. QuickTime Alternative is a smaller package and lacks the full complement of software included in Apple QuickTime, including QuickTime Player, PictureViewer, and any QuickTime Pro features. In addition, QuickTime Alternative does not run background processes such as the optional QuickTime Tray Icon from the official distribution.

QT Lite is a stripped-down version of QuickTime Alternative that contains only the base components, and does not install Media Player Classic

Media Player Classic

Media Player Classic is a compact media player for 32-bit and 64-bit Microsoft Windows. The application mimics the look and feel of the old, lightweight Windows Media Player 6.4 but integrates most options and features found in modern media players...

. It used to be maintained concurrently with QuickTime Alternative.

History

• On March 10, 2006, QuickTime Alternative 1.56 was released, which is the last version based on Apple QuickTime 6.0, and therefore the last version to support Windows 98
  Windows 98
  Windows 98 is a graphical operating system by Microsoft. It is the second major release in the Windows 9x line of operating systems. It was released to manufacturing on 15 May 1998 and to retail on 25 June 1998. Windows 98 is the successor to Windows 95. Like its predecessor, it is a hybrid...
  
   and Windows Me
  Windows Me
  Windows Millennium Edition, or Windows Me , is a graphical operating system released on September 14, 2000 by Microsoft, and was the last operating system released in the Windows 9x series. Support for Windows Me ended on July 11, 2006....
  
  .
• On June 28, 2007, QT Lite was introduced. QT Lite 1.1.2 published 2007-11-12 was the last version for Windows 2000
  Windows 2000
  Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
  
  , QT Lite 2.0.0 published one day later required Windows XP
  Windows XP
  Windows XP is an operating system produced by Microsoft for use on personal computers, including home and business desktops, laptops and media centers. First released to computer manufacturers on August 24, 2001, it is the second most popular version of Windows, based on installed user base...
  
  .
• On September 14, 2007, QuickTime Alternative 1.90 was released, which removes QuickTime Pro functionality and DirectShow filters, both of which were included in prior versions. Based on Apple QuickTime 7.2, QuickTime Alternative 1.95 is the first version that doesn't support Windows 2000
  Windows 2000
  Windows 2000 is a line of operating systems produced by Microsoft for use on personal computers, business desktops, laptops, and servers. Windows 2000 was released to manufacturing on 15 December 1999 and launched to retail on 17 February 2000. It is the successor to Windows NT 4.0, and is the...
  
   or CPUs without SSE
  Streaming SIMD Extensions
  In computing, Streaming SIMD Extensions is a SIMD instruction set extension to the x86 architecture, designed by Intel and introduced in 1999 in their Pentium III series processors as a reply to AMD's 3DNow! . SSE contains 70 new instructions, most of which work on single precision floating point...
  
  .
• On December 15, 2007, QuickTime Alternative 2.20 was released and it was based on Apple QuickTime 7.3.1.70. From this version upwards support for CPUs without SSE is restored back again.
• On September 3rd, 2009, QuickTime Alternative 3.2.2 was released. Based on Apple QuickTime 7.6.6.
• On July 15, 2010, both Quicktime Alternative and Real Alternative were removed from their main distribution website, and on July 25, 2010 QT Lite and Real Alternative Lite followed suit. The maintainer of these software packages, CodecGuru, refuses to discuss the reason for the removal, saying "that discussion is not wanted here." CodecGuru also actively deletes or edits any posts on the Codec Guide forum that mention the two codec packs and their removal. Repeated posting about the topic results in users being banned from the forum. CodecGuru stated in a forum post that "There are no links on the site anymore to stimulate the use and development of open-source alternatives, such as VLC
  VLC media player
  VLC media player is a free and open source media player and multimedia framework written by the VideoLAN project.VLC is a portable multimedia player, encoder, and streamer supporting many audio and video codecs and file formats as well as DVDs, VCDs, and various streaming protocols. It is able to...
  
   and ffdshow
  Ffdshow
  ffdshow is a media decoder and encoder mainly used for the fast and high-quality decoding of video in the MPEG-4 ASP and AVC formats, but it supports numerous other video and audio formats as well...
  
  , instead of the use of proprietary software."
• On August 16th, 2010 QT Lite 4.0.0 was released. Based on Apple QuickTime 7.6.7.
• On December 18th, 2010 QT Lite 4.1.0 was released. Based on Apple QuickTime 7.6.9