Dropbox is handy for secure file storage in the cloud and you can have open folders anyone can link to.

Flickr has been around forever and is designed for photos. You can do some editing and post processing on line with it, too. Many pros use it to sell their stuff.

Google, Amazon, and Microsoft have come up with their own plans, too, and you might already be signed up for them. Stuff I take with my camera I have to manually upload to Flickr, but stuff I take with my phone is automatically stored on Google's stuff.

It gets complicated, but they are all free and work well. No doubt you will get more suggestions.