Are you serious? You need to check the Steemit FAQs: Re Master Password and Keys read this from the official FAQs please:

Why should I be careful with my master password?

The master password is used to derive all keys for your account, including the owner key. If someone has access to your master password, they can steal your account and all of the tokens in it.

What are my different keys for?

Posting key - The posting key allows accounts to post, comment, edit, vote, resteem, and follow or mute other accounts. Most users should be logging into Steemit every day with the posting key. You are more likely to have your password or key compromised the more you use it so a limited posting key exists to restrict the damage that a compromised account key would cause.

Active key - The active key is meant for more sensitive tasks such as transferring funds, power up/down transactions, converting Steem Dollars, voting for witnesses, updating profile details and avatar, and placing a market order.

Memo key - Currently the memo key is not used.

Owner key - The owner key is only meant for use when necessary. It is the most powerful key because it can change any key of an account, including the owner key. Ideally it is meant to be stored offline, and only used to recover a compromised account.

You can check your keys under wallet/permissions: