Possible Duplicate:
Why not use HTTPS for everything?
I know the basic differences between HTTP and HTTPS that is related to secure HTTP communication.
I would like to know that why some of the websites are served on both HTTP and HTTPS? In one of my earlier project, same website was served over port 8443 that is for HTTPS and port 80 that is for HTTP.
When I login to website I see a URL starting with https://www.my.org.etc
After login, all other pages also appear with https://www....
, not a single screen is served over http://www...
.
Then why do we configure the application to be served over http at all? We can just serve the application over HTTPS only?