https is a URI scheme. https means that http has to be used but with a different default port and additional encryption/authentication layers between HTTP and TCP. It was invented by netspace corporations to help with encryption for security-sensitive communication, such as payment transactions.
and just to let you know it doesnt mean it on a server. The fact that its on the net kinda means its on a server of somesort.
when someone logs into housekeeping it will be https:// instead of http:// to show its a secure network this was implimented after the housekeeping attacks i believe to add security. Its the same with PECOS eProcurement (a bit like eCommerce but better) it will login on https:// but you cant go to https:// and see a site.







extra and intra (internal only) are the homepage tools which manage content adding and the RSS feads (like a site builder) and *** is an extranet not an extra net, an extranet is a private network, its like your schools intranet (accessable only in school) but you can allow external computers to access it.
its not a "type" of program or something and i think intra is housekeeping :S