website for notes

I am in need of a website for taking and sharing notes. It should have the functionality to attach files and images, while the design should remain minimalistic and clean. The website should be able to hold both personal notes, as well as collaborative notes amongst multiple users. Security and ease of use is important to me, so I would like the website to be easily accessible and secure. It should also be able to have an organized and efficient way to store notes, as well as the ability to easily create and manage notes.