Shockwave Player from Adobe is a legitimate add-on for web browsers and is required for sites that have online games and lots of animation and interactive elements. Shockwave and Flash are the technology behind the games, online graphics and fancy stuff of web sites these days, including YouTube movies. Here’s a tech support link from PBS’s Kids: ZOOM Tech FAQ | PBS Kids.
Shockwave is different than Flash. Flash is more common, but is less capable than Shockwave. And Flash and Shockwave can be confused as they are made by the same company. Adobe has a web page that describes the differences: What”s the difference between Shockwave and Flash?.
It’s safe to download Shockwave from the link on the PBS site, or go to this link with either Safari or Firefox, and you’ll get a link to download and install Shockwave: Adobe – Adobe Shockwave Player. Once you download it, you’ll need to quit your browser.
You can check your version of Flash Player at this link, and get the latest version, if needed: Adobe – Adobe Flash Player