Three Uses for MetaMask
MetaMask connects to the Ethereum netwrok and other decentralized ledge technologies, it can be seen as the interface between smart contract and cryptographic signer via a web browser extension
The fourth industrial age is beggining to take shape and the Web3 MetaVerse will have all the features of previous digital incarnations ranging from the http, html, javascript family of protocol. It will be just as disruptive as the dot com era as this time it replaces certain parts of the global economy with more secure and efficient processes

Three Web3 Integrations Using MetaMask
Login to Web3 Websites
Metamask can sign requests to confirm the identity of the person visiting the site, this can allow for custom integration whilst remaining relatively anonymous.
On websites with Web3 integrations then there is no username or password a crpyto wallet provide an accessible way of signing transactions similar PGP/GPG
Provide Premium Content
The team at Unlock Protocol have been working on a cryptographically secured paywall system, where visitors can pay to remove locks on premium content, they have integrations that work with over 40% of all websites on the Internet, including Discord, Slack, WordPress, Drupal and Firebase. It allows for subscribers to fund content directly with no third party, as once the lock is created there is an immutable link between the lock and wallet it has created.
Store ETH
After buying or earning ETH Metamask is a great place to store funds that are going to spent in a short space of time, for storing larger quantities of ETH it’s advisable to look at colder storage
Ethereum processing power follows in the AWS style for cost, paying for compute power on demand and being based on usage makes it efficient and sustainable with a reliable funding model. Every interaction with the Ethereum Network requires Gas money