Your need passwords to log into websites and services, and it’s hard to remember them. Since it’s a bad idea to use the same password for each different website — because if one site is compromised, hackers will have an email address and password that they can try on other sites — you need to ensure that your passwords are different, and hard to crack. (A recent episode of the Intego Mac Podcast talks about password strategies.)
Your Macs and iOS devices have a “keychain,” which is an encrypted file that stores your passwords and some other information. This file syncs via iCloud, so you can use the same passwords on all your devices. Here’s how Apple’s iCloud keychain works.
Read the rest of the article on The Mac Security Blog.