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This chapter is from the book

This chapter is from the book

What Is Open Source?

When most people hear the term open source, their initial reaction is, "What is open source? What does it mean?" Simply put, open source is software that has the following characteristics:

Source Code Availability

Open source is software that has source code available to its users. It can be downloaded at will and used or modified as desired, as long as its license requirements are observed. This differs significantly from commercial, or proprietary, software, which is distributed only in binary format to ensure that its intellectual property remains privately held by the software creators. Commercial software is delivered in frozen form: It must be used as delivered.


Open source means that the product's source code is available to all users.

Open source products are usually also available in binary form so that they can be used on common operating systems without needing to be compiled first. Of course, not every operating system will have a binary available, but the source code makes it possible for the product to be compiled for any operating system that does not have a binary version available.


Open source products are usually available in binary form as well.

Open source software licenses are far less restrictive in terms of how the software can be used. This does not mean that there are no conditions imposed by open source licenses. Open source usually allows an organization to use the software in any way it desires, but often requires that any changes made in the source code be shared with the user community and given to any customers of the organization that makes the change.


Open source licenses impose far fewer restrictions on users.

Zero-Price Software

Open source software is distributed at no cost (this is mostly true; see Chapter 2, "Open Source Business Models," for a discussion of open source products available for purchase). This makes sense because it reflects the reality of source code availability. There is no way to control distribution of a software product available in source form. If any attempt were made to limit the product's use by, for example, locking the executable onto a single processor, the source could be modified to take out that portion of the code. Free source implies zero-price software.


Open source is usually available without charge.

There is no charge for the source code either. In this way, open source differs significantly from freeware, a type of software open source is often confused with. Freeware is software distributed without a fee, but without source code access. Freeware creators tightly restrict the intellectual property rights to the software and offer the software on a "take it as it is" basis, in contrast to open source, which carries far less restrictive licensing terms and allows users to modify the product if they so desire.


Open source is different from freeware.

Freeware is often distributed on a "time-bombed" basis, meaning it is free for use for a certain period of time. When that period is up, the software stops working. If the user wants to continue using the product, a licensing fee is necessary to defuse the "time-bomb" restriction.

The fact that open source software is zero price offers tremendous benefits to users:

  • The common dilemma of wanting more installations than they can afford is avoided. Use of additional copies often increases the benefits of the software to the organization.

  • The availability of zero-price software encourages innovation. Expensive software forces IT organizations to purchase software only for proven applications. Lower costs allow organizations to experiment and develop new applications or even new lines of business. This allows an organization to take greater advantage of IT in running their business.

  • Zero-price software enables IT organizations to stretch their budgets farther and purchase software that they might not have been otherwise able to afford. The dollars saved by using free software allows funding for additional applications that might not have otherwise made the budgetary cut.

  • Zero-price software reduces overall IT costs, allowing an organization to make greater investments in other aspects of its business. Free software reduces the number of capital expenditure trade-offs that companies must make.

Free Software and Zero-Price Software

Readers who wonder why the unusual "zero price" term is used instead of "free" should be aware that some participants in the open source community have a very different meaning for the term "Free Software." The adherents of Free Software believe that computer software should be widely available with no restrictions placed on its use, study, copy, modification, or redistribution.

Most participants in the open source community do not share these beliefs, but instead feel that intellectual property should be made available according to the motivation of the creator(s). Much more information about Free Software can be found at the Free Software Foundation's Web site (www.fsf.org).

It might seem a bit confusing to use the term zero price to refer to the cost of open source software, but this alternative seems preferable to the potential confusion of using the term free. The term Free Software carries with it much more implication than zero price, which should be kept in mind. In this text, zero price refers explicitly to the fact that most open source products are available at no charge.

Open Source: A Different Licensing Model

All software licenses reflect the rights of the creator to control how the software is distributed. Software is a copyrighted entity that embodies intellectual property, and, as such, enjoys the legal protection of copyright law. Although copyright law is often used to restrict use of a product, the law can be used to enable wide distribution as well. Every piece of software is distributed under some kind of license, which controls the manner in which the product can be used.


Software licenses protect the intellectual property of the creator(s).

Open source licenses differ significantly from commercial software licenses. Commercial licenses restrict the use of the software as much as possible, to enhance the possibility of selling many licenses. In contrast, open source licenses are written with the aim of encouraging wide use, with very few restrictions placed on the use of the software.


Open source licenses are significantly different from commercial software licenses.

One way of viewing the differences in licensing practices between commercial and open source is that commercial software licenses are written to allow the software creators to harvest the value that users receive from the product. By contrast, open source licenses are written to allow software users to harvest the value from the product. As noted earlier, users are allowed to modify the source code if they desire to increase the value they receive from the software. Other benefits of open source licensing include the following:

  • Users are not restricted as to which or on how many machines they can install software. Commercial licenses typically control very tightly on how many machines software can be used. Being able to install as many copies as desired is a great benefit to users. As application use grows, it is easy to expand the number of copies installed for load-balancing purposes. Furthermore, organizations can install additional copies of open source software for training, testing, demonstration, and integration purposes. The flexible licensing terms encourage organizations to use software in ways that offer the greatest benefit to them. Strict licensing terms often restrict users from using software in ways that offer them the greatest possible benefit.

  • There are no restrictions on access to later versions of the software. Commercial software licenses often require large "maintenance" payments to enable user organizations to access patches, maintenance releases, and upgrade versions of the software. Open source software imposes no such restrictions.

  • The user communities for open source products are usually much larger than for commercial products. Because the products are available at zero price, many more organizations use the products. Large user communities offer many benefits to the developers and users of the software.

Open Source: Free Speech, Not Free Beer

Open source devotees often describe the importance of its licensing with the phrase "free speech, not free beer." The point of this phrase is that, although open source software is usually available at zero price, the critical aspect about it is that open source offers real freedom for software creators and users. Specifically, the "free speech" part of the epigram refers to the liberty that the users of open source have to use, modify, and distribute the software. This liberty is tied to the licensing conditions that make source code available to software users.


"Free speech, not free beer" embodies the beliefs of open source.

Source availability means that the uses someone can make of software are nearly unlimited. It can be copied. It can be modified for one's own purposes. The modified version can be distributed as well, if one chooses to do so. So, "free speech, not free beer" emphasizes the rights that accompany open source licenses and points out that these rights are not the same thing as zero-price software.


"Free speech, not free beer" emphasizes the rights that accompany open source.

"Free speech, not free beer" might overstate the appeal of free speech and understate the appeal of zero-price software to most open source users, just as New Hampshire's motto "Live Free or Die" might be only a small part of the residents' enjoyment of the state—the larger part being the low taxes they pay. However, open source licensing terms make possible the free availability of products as well as underlying the other benefits of open source software. The topic of Free Software is addressed in the "Free Software and Zero-Price Software" sidebar as well as in the licensing section of Chapter 3, "Open Source Risks."


Not all users are focused on the free speech part of "free speech, not free beer."

Conditions of Open Source Licensing

Just because open source products are available with an unrestrictive license does not mean that there are no licensing conditions at all. Typical license conditions include contributing any source changes back to the main source base and distributing source changes to any customers of the organization that modified the code. The specific conditions depend on the type of open source license that accompanies a given product. The topic of open source licensing is addressed at greater length in Chapter 3, "Open Source Risks."


Open source does carry licensing restrictions.

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