If you are going to run an e-commerce site, you will need to have a picture of your product. After following Odoo's tutorial, you will be prompted to add a picture for the product, as shown in the following screenshot:

When you're presented with Odoo's picture selection wizard, you have the option to choose pictures from a gallery, your own computer, or even from a URL:

Notice the UPLOAD AN IMAGE and Add an image URL buttons near the top. You will probably use these more frequently than the built-in gallery pictures that Odoo provides.

We are going to use the UPLOAD AN IMAGE option to add an image of a simple blue t-shirt. We are using Chrome on Windows 10 to upload Blue_Tshirt.jpg, which was obtained from the creative commons image library:

Once you click Open, the page will refresh and you should see that your product image has been successfully uploaded, as shown in the following screenshot: