To upload new files such as images and videos to your media library, navigate to Media in your Sidebar and Select Add New. This takes us to the multifile uploader. You can upload files simply by by dropping them here, or by clicking Select Files, which will show a drop down menu where you can choose your files. If your browser is having trouble using the multifile uploader, there is an option to use an older version of the Uploader that is easier on browsers. If we drop a file in here, a progress bar will pop up. When it finishes, you can click Edit. This will bring us to the Media Editor where you can make modifications. As you wish.