Adding entities, linking to other entities

Hi

I use to program desktop/ client server windows systems. If someone need to store a list of data against a company, it was relatively easy to manage - create a new table, then link it 1 to many to the company table - at it's most basic

So with CRM I've got our clients within Accounts. I want to store a list of info against the accounts relating to what hardware they have installed.

Can I do this ?

Can I just create a new entity and then link it to accounts ? Any quick way to show/do this

thanks

Mat