We have 2 options :

1. Delete

2.Truncate

Delete : It is DML concepts.

Syntax: Delete from <table_name>;

Example: Delete from emp;

Explain: The above query will delete all the record from the tale. Supose need
to delete the particular record from the table ,we can give the condition.

Syntax: Delete from <table_name> where <condition>

Example: Delete from emp where emp_no =101;

Explain: By default You gave the condition 101 instead of 1001. You can Rollback
and get the 101 record before doing commit.

Truncate : It is DDL commend.

Syntax: Truncate Table <Table_Name>;

Example: Truncate Table Emp;

Explain: The above query will delete all the record from the table. Suppose need
to delete the particular record from the table, we cannot give the condition.

Once we truncate the table we cannot Rollback.

DROP : Remove the table from data base.

Syntax: Drop Table <Table_Name>

Example : Drop Table Emp;