Well that depends.
- For accounts that allow Guest access (that's most) the answer is No.
- For accounts that disallows Guest access the answer is Yes. You will have to register or be invited (in some cases) before you can search.
Typically (when Guest access allowed) You can search through the assets in the library without registering.
However, irrespective of the above, you will need to register and login in order to download, save, share, send assets OR to view assets that are only available to registered users.
Happy branding :)