Difference between Customer and Client

Difference between Customer and Client:
Many people use the words "client" and "customer" interchangeably; they say there is not much difference between them.
According to Dictionary.com:

• Customer: a person who purchases goods or services from another; buyer; patron.
• Client: a person or group that uses the professional advice or services of a lawyer, accountant, advertising agency, architect, etc. The difference between them can at first seem quite confusing. However, the difference can best be seen in terms of an ongoing business relationship.
  See the next table to understand the difference.

CUSTOMER
vs.
CLIENT

Both are considering "a person that purchases goods or services"

It is a person that purchases goods or services from another person or company.
It is also called buyer or patron.
I.e. when you buy milk at the supermarket, you are a supermarket customer.
It is a person that purchases goods or services, AND is under the protection and engages the professional advice / knowledge of another person/business leader.
I.e. when you employ the services of a lawyer, you are his/her client.

Implies a short-term, primarily economic relationship.
It is a patron who buys something, and the relationship used to finish after that.
If someone is a longtime customer, he/she can be recognized as “our best client”.
Implies a long-term, protective, loyal, and ongoing business relationship.

You, as a company emphasis your business on selling; thus your goal is to get the customer to buy something.
You, as a company emphasis your business on serving; thus your goal is to look out your client needs and provide them with the best service you can.

Your aspiration should be to build sustainable relationships with clients who value your professional advice rather than to find customers who make a one-time purchase simply because you have what they need.
If a company fails to keep their clients as such, they could turn into customers. Companies do not want this to happen because customers are more likely to use other businesses next time, than clients are. It actually would affect your business if a client left your company, whereas a customer would not.

As the clients are people who seek advice, companies tend to pay more attention to them than they do to customers. For that reason in today's business world, you can find companies that actually have changed the name of their Customer Service department to Client Service.

CONCLUSION
There are differences in the definitions, but also there are biggest differences between companies who sell to customers and those that only serve clients.

You must know the difference, because it can affect the way in which you do business, and create loyal client relationships to keep your business alive.