This icon is used a lot to verify you are not a robot. It is a reduced rectangular box that is filled with a white background and floating letters and numbers inside it.
This CAPTCHA icon is made in flat color style
. This format was developed by Icons8 designer team and became immensely popular for use in web and mobile applications. Feel free to download this icon in PNG format for free, or unlock other formats for $5. Unlike other icon packs that have merely hundreds of icons, this monster icon pack contains 5,900 icons, all in the same style and quality.