Dropbox is a great service that helps you keep your files safe in a cloud, synced with other users and accessible from anywhere: your desktop, laptop, tablet or phone. We work with it a lot to exchange content with clients – especially during the website building process.
You can work Dropbox it in two (integrated) ways.
1. Online at the Dropbox website: sign in and create, access and share your folders in your account online.
2. Download the Dropbox app to your device: once installed, Dropbox acts like a normal folder on your computer where you can keep files, but it’s special in that everything you put into that folder is automatically backed up to the cloud and synchronized with other users you’ve assigned to the folder and in your Dropbox on any of your other devices its installed on.
WikiHow gives a great step-by-step guide to getting started and sharing files with both methods.