preventative maintenance in navision service mgt

Dear All,
I am currently studying service management. In a demoscript service management, in page 16, I read as follows:

So, it seems navision can handle preventative maintenance, however in ( , I’ve read as follows:
Preventive maintenance (PM) has the following meanings:

Could you explain to me what are the functionality regarding to the wikipedia statement, I mean in service management, I could use what tables or form to conduct the preventative maintenance…?
I expected your answer so much. tku


Effectively the service management are covers the statements made. You have contracts and orders for scheduled (preventative) or call outs (reactive) and the processing of the work involved in these areas covers your statements.