User creation on MySQL and giving Privileges

mysql> CREATE USER 'good'@'localhost' IDENTIFIED BY 'man';

Query OK, 0 rows affected (0.16 sec)

mysql> GRANT ALL ON iot.* TO 'good'@'localhost';

Query OK, 0 rows affected (0.18 sec)

mysql> FLUSH PRIVILEGES;

Query OK, 0 rows affected (0.12 sec)

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Here localhost means that  Data Pushing Application and MySQL DB Server both are on the same System.

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If Data Pushing Application  and MySQL DB Server are on different Systems.

Then we give  the permission to that  Data Pushing Application like ..

CREATE USER 'good'@’2.16.1.200’ IDENTIFIED BY 'man';

GRANT ALL ON iot.* TO 'good'@'2.16.1.200';   (Here 2.16.1.200 is the Data Pushing Application IP Address.)

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If we want to access any host(IP Address of any System) then

 CREATE USER 'good'@’%’ IDENTIFIED BY 'man';

GRANT ALL ON iot.* TO 'good'@'%';   (Here % means that Any host can access our MySQL Server DB)

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