In this chapter, we discussed the importance of language in system design and how precise and unambiguous terminology brings clarify and shared an understanding of the domain for business people and developers. We also looked at how different industries use the same words to express different concepts and what consequences this has for domain modeling.

The code sample in this chapter showed how unclear language can make the implementation more complex and less understandable. By introducing a better language to the code, we made it much more clear and also shorter and more concise. We made some implicit concepts more explicit and it helped a lot to get a better understanding of the business and improved the code quality. We also discovered many verbs that became part of the language, which is a very important addition to a glossary of nouns that is often being seen as the only important part of the domain model.

This chapter introduced the term ubiquitous language, coined by Eric Evans. We emphasize the fact that the ubiquitous of the language is not in its wideness but in its precision and the fact that it is being used for all artifacts of the software development process—from initial discussions, through modeling and design, to code and tests.

We looked at how words change their meaning between different contexts and how context switching can negatively impact productivity. Using our sample domain, we went through a couple of examples, how contexts are being discovered during the modeling process and in conversations between developers and domain experts. 

In the next chapter, we will explore one of the most popular techniques for domain modeling and go through some practical tips on how to organize useful workshops between domain experts and developers.