Icons are a great way to communicate without words creating more visually appealing presentations instead of just slides of text. Below is an example using free to use icons.
A great place to look for icons is: https://www.iconfinder.com/. This site allows you to tailor your search for free icons. You can download the files in different formats. If you choose PNG as the file type this will keep the image transparency, meaning it won’t add a white background to the image.