configuration db:
This db contains informations about the sharepoint databases,iis websites and web applications,trusted solutions,web part packages,site templates and farm settings of sharepoint farm settings.This must be reside on where the Central Administration content database residing.This is read-heavy database once production begins.
Content db:
this contains all of the site contents like lists,libraries,properties of webparts,audit logs,user names and their rightes on the site.It can contain multiple sites or single site.If single database larger than microsoft recommended limitaion 200GB then storage must be carefully consider.Sql enterprise edition's table partioning could be used.Part of databases can be reside different RAID array.
Property
Crawl
Search Administration
Web analytics reporting
Web analytics staging
Profile
Synchronization
Usage
Business connectivity Database
Application Registry
Subscription settings
Social tagging
Secure store
Word automation services AND performance point.