I wondered what exactly --load option does in odoo in server "help" i able to find only this line which doesn't explains fully about option,
--load=SERVER_WIDE_MODULES(Comma-separated list of server-wide modules.)
and what are server-wide modules?? and what is benefit of using this option ???
Server wide modules means which has loaded or installed at server wide.
When you start odoo then first time you will open link like : http://localhost:9090/web/database/selector
It means you did not created any database but web module is loaded automatically when odoo is starting.
You can add other module as server wise modules using following method.
This may help you.