What is a one-sentence summary of the following article?
You can add, delete, edit, or view files in your Dropbox folder from any computer on Dropbox.com. Click Sign In at the top-right corner of the screen to sign in to your account. Once you’re in, you’ll see the contents of the Dropbox folder on your computer. As long as the computer you’re on supports the file type, you should be able to open and edit the files in your Dropbox without issue. To add new files from another computer, click the blue Upload Files button on the right side of the screen, then follow the on-screen instructions to add your files. The next time your Mac connects to the internet, the files you uploaded will sync to its Dropbox folder.

Summary:
Go to https://www.dropbox.com. Sign in to Dropbox. Click a file to view it. Upload new files.