Metamask* Extension:

MetaMask is a Chrome extension that lets you access Ethereum enabled distributed applications, or "Dapps", and manage your own identities and transactions.

Metamask is a cryptocurrency wallet and gateway to blockchain applications available as a browser extension for Chrome, Firefox, and other compatible browsers. Developed initially as a simple Ethereum wallet, Metamask has evolved into a versatile tool that allows users to manage their Ethereum assets, interact with decentralized applications (dApps), and participate in blockchain-based protocols and smart contracts.