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As a starter understanding how to secure my account is very important, because any misplacement or loos of the keys most importantly my master key is disastrous .

With the help of Mr Charles @focusnow, I have carefully secured my keys following the creation of my account for easy access whenever the need arises.
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There are four different keys generated and they have different permissions, I know their functions and restrictions which are:

POSTING KEY

The posting key is used for social networking actions, like posting, commenting and voting. This key has a limited set of permissions and it is not able to be used for monetary action that means you won't lose money if someone discovers your posting key, nevertheless the posting key must be kept safe.

Posting Key permissions:

• Publish a post or comment
• Edit a post or comment
• Upvote or downvote
• Resteem content
• Follow people
• Mute accounts

Active Key

This key has additional permissions for more sensitive monetary-related actions, like transferring and exchanging tokens.
In the process of performing wallet related action, you may be reminded to authenticate using your Active Key. Anyone who has access to this key can take your tokens. To avoid losing your tokens you must store and keep this Key safe.

Active Key permissions:

The Active key is used to;
• Transfer tokens
• Power STEEM up or down
• SBD conversion
• Vote for witnesses
• Place an order on an exchange
• Certain profile changes
• Publish a Witness price feed
• Create a new user

Owner Key:

The owner key has the power to change the other keys, it can be used to recover your account. It is the most important key and should be securely saved offline

Owner Key permissions

Owner Key has these functions:

• Reset Owner, Active, and Posting keys
• Recover your account
• Decline voting rights

Memo Key

The Memo Key is only used to encrypt and decrypt private messages that are sent through the blockchain, and for this it is not commonly used .

Memo Key permissions include:

• Send an encrypted message
• View an encrypted message

Finale
If your Master Key is lost, your account cannot be recovered! Therefore you should have an offline copy of your Master Key because it is the most powerful among all the Keys. Do not in any way disclose your keys with any third party site or app if you are not sure of the app or site.

Special thanks to you @cryptokannon for your efforts in bringing this achievements, it has been a great source of help.