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Achievement 2 msarwar45045 Task : Basic Security on Steem

Posting key:
This key is used for logging in to perform all social operations which include post, comment, follow, unfollow, subscribe, and vote. So it is very essential to keep it safe.

Active key:
If you want to transfer funds from one account to another account, the active key is used. Another use of this key is to convert sbd into steem tokens.

Memo key:
For encrypting and decrypting the message when transferring funds which are sent on steem.