Metamask login allows you to store Ether and ERC20 tokens in your pockets. MetaMask internet extension allows buyers control non-public keys to Ethereum via internet browser. You can access the app browsers that are available today from your internet. MetaMask login accounts allow Ethereum Decentralized apps(Dapps), to run without even walking through complete Ethereum nodes to your browser. This is in case you don't wish to install and sync the entire Blockchain for your device. MetaMask's top goal is to make Ethereum buying and selling easy and accessible for everyone. https://sites.google.com/view/metamaskloginwallet