What is a domain?

Let’s look at polish definition, which best suits our considerations:

Domain is the scope of interests or activities of a person, institution or field of knowledge (source: https://sjp.pwn.pl/)

The domain of the company is everything the company does.

The domain is compound of subdomains, which are a scope of activities/functional areas like marketing, selling, and finance.

What is subdomain?

“a subdomain is a domain that is a part of another (main) domain”.

Subdomain is part of the domain e.g. marketing. A subdomain is also a domain, but a more specialized domain – particular scope of interests or activities.

Examples

Best explained with examples. The first example comes from my life. My domain is everything I do, which is taking care of my family. Subdomains are individual activities in the domain of family care:

Let’s look at another example. The company sells toys on the internet. The company’s domain is sale of toys. Now think a little about what is needed to sell toys on the internet … we need the product cataloge, placing orders, payment, delivery etc. This way we define subdomains:

Domains can be nested

(Sub)domain can contain other (sub)domains.

The marketing domain can contain some areas/subdomains that we want to present because they are important or special for company business.

Domains can overlap

In an organization, when two departments cooperate with each other, carrying out some business processes together, we draw domains in this way:

There may even be such a situation:

This will mean that there are many common interactions, common processes. This is very important information that affects the designed solution.

Domains can change

Don’t spend a lot of time to perfectly discover domains. They may change during the project. In the case of startups, it is even certain. In case we do not have all the requirements or the requirements change, the domains will most likely change. It is important to make changes on an ongoing basis so that everyone is aware of what has changed and how.

Present what is important

Use your imagination to present visually many things eg. including the cooperation of domains by overlapping, the importance of domain by thickness, domain size, business value, etc