Virtual worlds and metaverses are immersive online environments that allow users to interact, create, and explore. They can be games, social platforms, or virtual reality experiences. Examples include:

1. _Second Life_: A virtual world where users create avatars, build, and socialize.

2. _Minecraft_: A popular sandbox game that allows players to build and explore blocky worlds.

3. _VRChat_: A social platform that lets users create avatars and interact in virtual reality.

4. _Decentraland_: A blockchain-based virtual reality platform for creating and exploring 3D environments.

5. _The Sandbox_: A decentralized platform for creating, selling, and owning digital assets and experiences.

6. _Roblox_: A user-generated game platform that allows players to create and explore games.

These virtual worlds and metaverses offer new opportunities for:

- Socializing and community-building

- Creative expression and content creation

- Gaming and entertainment

- Education and training

- Commerce and entrepreneurship

- Virtual events and experiences

They also raise important questions about:

- Identity and anonymity

- Privacy and security

- Governance and moderation

- Economic and social inequality

- Addiction and digital wellness

As virtual worlds and metaverses continue to evolve, they will likely shape the future of online interaction, creativity, and innovation.