I'm no tech wizard so I'll state it in terms I understand. Qora runs in your browser, just like Steemit, but you need the client running for the decentralization. The client has a menu option to open up your browser and establish a connection to the blockchain, and everything after that is browser based while the client runs in the background. You can even make the client run as a background service.
If you have more technical questions, it would be best to contact Vrontis or one of the other devs in Qora's slack channel or BTT thread.