[postgis-users] complete newbye

[william]

I'm new to databases and i'm making a short article on postgresql but 
i'm not sure i can name things :
i want to know why does a software like mapinfo only an display tables 
and not maps
i want to know why it does work well with PgArc
i want to understand what is the data model in Postgis and if it is the 
same as in the OGC description

Excuse me for my ignorance
bye for now