what are domain object and service entity?

Hi
thank you for reading my post
what are Domain objects and service/business entities ?
I know DAO and DTO but i can not understand thie two domain object and service/business entities.

Thanks

"Domain" usually refers to something in the business world. We talk a lot about domain objects in analysis. For example I work in insurance and our system has domain objects like Contract (policy) and Party (owner, insured, etc).

"service/business entities" is not a term I'm familiar with. I could guess, but that wouldn't be real helpful to you. Did you find it in a book or school notes or something? Give us a little more context around how it's used and what you think it means.

Hi
Thank you for your answer
I can not find the link that i read this but i remember some of its important sentences :

if we have a customer with its which has some properties , we can add methods to it for saving the customer to database , retriving the customer details from database ( initiate a customer based on PK) and methods to perform other tasks.
it was first way which is similar to EJB , the other one was like this :
we have a customer with properties and another class which do savecustomer , loadCustomer , .....

i remember that respective author named the second approach business entity .

now i want to know more about second and first approachs and i want to know which solution is better ?

Thanks

i want to know which solution is better

There is no generally "better" solution.

Encapsulating the data and fetch/store code together can be a good choice if these things are tightly bound together, share little with other business objects, and will usually move/change together.

Separating the data and fetch/store code can be a good choice if many business objects use common fetch/store facilities which don't move/change at the same times as the business objects.

Can you tell us any more about the needs of your a system you are considering using these for?

I want to develop a web application based on jsf and EJB3 as both of them are good technologies as far as my reaserch tell.
the web application will have about 15 Database tables , certainly they have some relation together.
application will have data entry , retrieve , reporting , user management (login/logout/register) .