Without a domain name your website URL / web address, may include the name of the ISP. For instance, if you were to take advantage of the free web space that you get with "free" ISP's, your website address could be something like...
Furthermore, your business email addresses may be something like...
Having the name of an ISP in your business address does not look very professional.
If you register a domain name (i.e. using the name of your business or company or organisation) you could have an address on the Internet that is clearly yours and adds a sense of professionalism to your Internet presence.
As long as it is available, you could have the website address you like.
We can register domain names on your behalf, please feel free to 'Contact Us' for availability and pricing.