Commercial software:

Open source software:

Do not get the source code, you can not change.
You pay thousands of money on software and higher.
You pay fees for each copy of software.
Support can only get from a dealer.
It developed a camera with one company.

You get the source code, you can edit it.
And upgrades of the software is freely spreadable, you can get a slight charge.
You can make as many copies as you want.
You can get support from anyone.
It is developed through the Internet, the cooperation of several companies and individuals. You can also contribute to its development.

The complete definition of open source software, see Open Source Initiative OSI - The Open Source Definition

History:

Although the history of open source began earlier, the first truly successful product of the Linux operating system, developed since 1991. With advancing Linux users grew, the number of open source applications under the applicable operating system. But now open source software is also available on MS Windows. Even traditional commercially oriented companies (IBM, Apple, HP, Sun, Silicon Graphics ,...) begin releasing its software as open source.

License for open source software

Under copyright laws, software purchased but licensed.

Licences for commercial software using copyright to restrict use of the program. Open source licenses work very differently, so that they are also called "Copy Left" instead of "Copyright".

Two basic licensing models:

"GNU General Public License "or" GNU GPL " used since 1983. It was created by the organization "Free Software Foundation, which deals with the support of free software. Basically says this:

1st You have the right to the source code of the software.
2nd You can redistribute the software.
3rd If you Software to someone else, you must provide the source code.
4th If the software is modified, or combined with other software, you need the source code of all software available to the public.
5th You can change the software license and distribution must include the license and copyright.

"BSD " is a short name standing for another license created by a team of Berkeley Systems Development at the University of Carolina at Berkeley. This license is even simpler, containing only points of the second and 5 of the GPL.

There are many other licenses: LGPL IBM Public License SISSL, Apache License, MozPL, NCSA License Common Public License, and so forth. But all result from any of the above two models. Index and full text of the various licenses available at Open Source Initiative OSI - Licensing

Which programs are open source?

This is a short list of familiar programs to form ideas of what is available. Complete list is much longer, and still growing.

Operating Systems:
Desktop software:
File Sharing:
Web Sites:
Databases:
Web Browsers:
E-mail software (client, server):
Graphics:

Linux, FreeBSD
OpenOffice.org, AbiWord, Gnumeric, KOffice, GnuCash
Samba, NFS
Apache, ZEUS
PostgreSQL, MySQL, SAP DB, Rekall
Mozilla, Konqueror, Galeon
KMail, Mozilla Mail, Evolution, Sendmail
GIMP, Scribus, Kontour

And many others:
KDE, Gnome, Ghostview, XCDRoast, PHP, Python, cervisia, TeX, DocBook, Webmin, aktion, OpenSSH, Iptables, WuFTP, ProFTP, Gaim, Compiere, TUTOS, JBoss, phpgroupware, procmail, Ogg Vorbis, Kate, Quanta Plus BIND, Emacs, VI, Nautilus ...

The 4 most popular:

Office Suite All-in-one for beginners and advanced users.

Four excellent tools: Writer (word processor), CALC (spreadsheet), draw (graphics) , Impress (multimedia presentation)And Base.

No royalties. You can install it on an arbitrary number of computers at home, at work, give it to friends ...

Now, the Slovak version of the spellchecker.

Read also creates a commonly used file formats including Microsoft Office.

Powered 98/NT/Me/2000/XP/Vista Microsoft Windows, Linux, FreeBSD, Solaris and Mac OS X (under X11).

Now also exports to PDF and image files into the format. Swf (Flash) and HTML.

Thanks to the xml format and compressed files are much smaller than you might expect.

Presents it to you next presentation created with OpenOffice.org Impress.

Presentation

To avoid some of the other issues:

StarOffice is a commercial version of OpenOffice.org applications, granted by Sun Microsystems, which sponsored the project OpenOffice.org.

OpenOffice.org reads and creates a MS Office file formats with 95% accuracy.

OpenOffice.org is resistant to MS Office macro virus.

100,000,000 downloads and users worldwide. Some European and South American countries introduced it to the state or government.

Instructions to programs and discussion forums
visit OpenOffice.cz

GNU / Linux

GNU / Linux is a Unix-type operating system originally created by Linus Torvalds, a student of Helsinki University. The first version 00:02 Linus released in 1991. He worked until 1994, when it was released version 1.0 Linux kernel. Development of Linux continues.
Linux is a kernel, but requires support programs. Most of them are granted the Foundation's GNU project, Free Software Foundation, and therefore the whole is called GNU / Linux.

GNU / Linux is developed under licensein GNU General Public License and its source code is freely available to everyone. It is often considered an excellent, inexpensive alternative to other more expensive operating systems.

GNU / Linux is distributed through various distributions. The best known are Red Hat, Mandrake, Debian.
Currently, there are the so-called distribution. live CD. Boot directly from CD without installing to your hard disk. These include Knoppix and its Czech version DaNiX.

With its functionality and availability, Linux has become popular worldwide, and many programmers to adapt the source code to their individual requirements. There are many projectsTo adapt Linux to various hardware configurations and purposes.

GNU / Linux is installed on roughly 4% of workstations (Gartner Dataquest) and 10-30% of the server (depending on whom you ask).

Mozilla is a full Internet package that includes a modern web browser, an intelligent email client, IRC chat client and HTML editor - everything you need for the Internet in one application.

Firebird and Thunderbird versions of Mozilla's lightweight - only the browser / email program only. Besides these, there are various additional projects or Mozilla. built on Mozilla, such as a calendar plugin for Macromedia Flash.

Navigator Allows you to browse through cards - in one window you can open several pages.
You can disable unwanted windows and overlay images.
On the site you can also navigate using the keyboard.

Mail client includes support for recognition of junk mail (spam).
You can organize your mail using labels, filters and previews.
Multiple accounts allow you to organize all your mail through one interface.
The risk of viruses spreading uncontrollably with a minimum because the application does not use any undocumented features of the operating system used by viruses.

The site projektu http://dictionaries.mozdev.org available dictionaries for 40 languages, including Slovak.

Apache

It is the most popular web server used by over 60% of web servers worldwide (Netcraft). Many Apache servers running on open source operating systems. So you use open source, though you may not know about it.

In fact, most Internet-based open source software.

Many organizations use open source software:

IBM, HP, Sun Microsystems, Inc. Verizon., Burlington Coat Factory, NextBus, Inc. O'Reilly., Amazon.com, The New York Stock Exchange, Nokia Inc.., Google.com ... and what you may be surprised, Inc. and Microsoft.

Price: 30 USD