Shockwave Player was a browser plugin developed by Macromedia (later Adobe) that allowed users to view multimedia content created using Macromedia Director. This content could include interactive games, animations, and presentations. Think of it as a sort of early, more powerful version of Flash, though it predated Flash[SQ]s widespread adoption.

However,

Shockwave Player is essentially obsolete now.

Due to security vulnerabilities and the rise of more modern web technologies like HTML5, Adobe discontinued support for it years ago. Modern web browsers no longer support plugins like Shockwave, meaning you cannot run Shockwave content on most current systems. Any websites relying on Shockwave content will be broken or require a very old, insecure browser to function.