Open Source applications cover nearly all kinds of use. There is a little tendency toward communications, probably while they are the hearth of the community. This Entry attempts to collate the 'best of breed' open source projects.

Network applications

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  Apache Web Server.
  

  
  The most used webserver in the world. Quite simply without it the web would be a much smaller place. Cross-platform.
  
  
  

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  BIND DNS Server.
  

  
  The programme that turns www.bbc.co.uk into a numerical pointer that computers can understand, allowing you to find the webserver on which websites are hosted.
  
  
  

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  Mozilla Internet Suite.
  

  
  A mostly standards compliant (usable) web browser, considered to be far in advance of the industry leading Internet Explorer, a very competent emailer (with various ahead-of-the-game features), a standards based web authoring programme, an IRC client and even advanced tools (such as a javascript debugged) for web programming. Cross-platform.
  
  
  

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  Mozilla Firefox.
  

  
  Arguably the best next-generation stand-alone browser, fast, efficient, extensible and standards compliant. Its popularity has been growing fast. Cross-platform.
  
  
  

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  Samba
  

  
  Arguably the best remote acess network filing system. Not to be confused with a peer to peer file sharing system. It allows Linux and Unix networks to connect to Windows networks.
  
  
  

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  Sendmail or Exim
  

  
  The two best email transfer programs, although the question of best depends on what for. Exim is considered the easiest to configure, while sendmail is considered the most powerful.
  
  
  

Office Applications

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  Evolution Emailer and PIM.
  

  
  Highly efficient email client and personal information management tools, with loads of advanced features such as Virtual Folders, similar to Microsoft's Outlook.
  
  
  

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  Emacs Editor.
  

  
  Far more than just an editor, you can do just about anything in the universe with this tool. It is a word processor (using LaTeX and generating pdfs). It is a text editor (html, XML, CSS etc), it's a Wiki and blogging tool, calendar, diary, reminder handler etc.
  
  You either love it or you hate it. Its main rival is...
  
  
  

• Vi(m)

  
  Reputedly the ultimate geek's text editor, and the original Unix text processing tool. Useful to learn in a limited-resource Unix environment.

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  Openoffice.org Office Suite.
  

  
  Some people considering it better than the leading competitor, Microsoft Office, there are many features that MS Office lacks that makes this suite a winner, such as exporting to PDF and Macromedia Flash, though some other possibly useful functions are missing. Cross-platform (has Linux, Solaris, Windows and Mac OS X versions). Its commercial cousin is StarOffice from Sun Microsystems, which includes a database application comparable to Microsoft Access, although the upcoming OpenOffice.org version 2 will feature this program too.
  
  
  

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  MySQL
  

  
  A relational database which is magnificently scaleable and used on a vast number of dynamic websites, such as in e-shops, often in conjunction with the PHP programming language.
  
  
  

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  Gaim Instant Messaging Application
  

  
  Gaim is available for both Linux and Windows. Its major advantage is that supports almost all IM protocols, including MSN, ICQ, AOL and Yahoo. It also features a tabbed interface.
  
  
  

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  Jabber/XMPP
  

  
  Instant messaging protocol - it is largely considered to be very flexible with its distributed, extensible architecture, and its server-side solution to connecting to other protocols (via "gateways"/"transports").
  
  
  

Hollywood has been framed by Open Source animations...

Multimedia Applications

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  Cinepaint
  

  
  A program which used to be known as film gimp due to being an offshoot from the standard graphics program "The Gimp" The 'Gnu Image Manipulation Program' was used for films like Scooby-Doo, Stuart Little, Sixth Day, Dr Dolittle 2, The Fast and the Furious 2 and Stuart Little 2.
  
  
  

• OpenGL

  
  A cross platform 2D and 3D 'application programming interface' (API) used for visuals, modelling and games. Supported by most vendors of graphics hardware and prefered over Direct 3D (an alternative API directed at games development) by companies such as idsoftware for its flexibility.
  

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  Ogg Vorbis music format.
  

  
  Open source, patent-unemcumbered music file-format. A sort of advanced MP3 equivilent, free to use, create, and incorporate into other things, and reportedly sounds great even with low file sizes. Cross-platform.
  
  
  

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  FLAC audio format.
  

  
  Free Lossless Audio Codec, for compressing audio without losing any information. Cross-platform.