Image Dimensions Improve SEO
When uploading images to your website, you can specify a width and height for them. A web browser will begin to display a page even before images are downloaded, provided that it knows the dimensions. Specifying these dimensions can speed up page loading and improve the user experience, all of which Google loves! Without image dimensions, when the browser runs into an image, the browser has to pause loading the page, load the image, then continue loading the page.
Below is a screenshot of of the image dimensions entered in the HTML code on a WordPress image placement.
FYI – WordPress uses widgets to place items like images on the side columns of the website.