Did you know that when you are uploading files to your library, you can upload multiple files all at once? When dragging and dropping files, you can either select multiples to drag or use Browse your Computer to get multiple files at once.
Hint: Click on the first file that you want to upload. If you wish to then select all up until another file (meaning you want all files uploaded), hold down the Shift key on your keyboard. This will select all files from the first one you clicked on to the last one you click on. If you want to select individual files and not highlight all of them to upload, use the CTRL (Command if you are on a Mac) key, you can then click on each file that you wish to upload. If your images are in different folders, you can always select the files from one folder, then click to Browse More Files at the bottom of the window to select files from another folder.