Here is the key difference between an external table and managed table:
In case of managed table, If one drops a managed table, the metadata information along with the table data is deleted from the Hive warehouse directory.
On the contrary, in case of an external table, Hive just deletes the metadata information regarding the table and leaves the table data present in HDFS untouched.
Note: I would suggest you to go through the blog on Hive Tutorial to learn more about Managed Table and External Table in Hive.
