What follows is not my own work but rather a post I came across from Maria Varzamis on the Sophos Naked Security blog. Maria uses LastPass herself so, when she explains in detail how it works, including advantages and disadvantages, she is writing from firsthand experience:
By Maria Varzamis
A few days ago I wrote my plea to those of you who may still be on the fence about using a password manager. I hope I’ve convinced you to at least give it some serious thought. If you’re ready to give one a try, today I’ll introduce you one of the many available password managers out there.
For the sake of full disclosure, this one happens to be the one I use, but I encourage you to do your own research and use the password manager that best suits your needs. Many people prefer to use password managers where your passwords never see the internet, while other people find the advantages of cloud storage worth the risk.
Password manager: LastPass
Where it stores your passwords: LastPass locally (on your own device) encrypts your passwords, and then stores that encrypted data in “the cloud,” a.k.a. somewhere else on the internet.
Security: Account data stored in the LastPass “vault” (including your passwords) is encrypted using AES. Connecting to the LastPass service can optionally be protected by 2FA for additional security against unauthorized logins.
Cost: It’s free to use the password manager’s basic features, like the browser extension and password vault. Multi-user credential syncing and the LastPass app access require paying for a premium plan…
Maria’s article goes on into much greater detail, read the rest of Maria’s informative article here: Try a password manager: how to get started with LastPass