Google Reverse Image Search
Google Image Search can be used to find the same or similar image to one you already have across other websites on the internet.
To do this, you can either upload an image on your computer for Google to check, by clicking the “Upload an Image” tab and finding the file on your computer, or by copying the url of an image and pasting it in the “Paste Image URL” tab. To find the url of an image, right click it on the website, and click “Copy file location”.
If you want to do a reverse image search on your phone or tablet, then you can use the Chrome application to find the image, and when you do touch and hold the image, then tab the box that appears with the text “Search Google for this image”.