mysql>help contents;
You asked for help about help category: "Contents"
For more information, type 'help ', where is one of the following
categories:
Account Management
Administration
Data Definition
Data Manipulation
Data Types
Functions
Functions and Modifiers for Use with GROUP BY
Geographic Features
Language Structure
Storage Engines
Stored Routines
Table Maintenance
Transactions
Triggers

mysql>help Data Definition;
You asked for help about help category: "Data Definition"
For more information, type 'help ', where is one of the following
topics:
ALTER DATABASE
ALTER TABLE
ALTER VIEW
CONSTRAINT
CREATE DATABASE
CREATE INDEX
CREATE TABLE
CREATE VIEW
DROP DATABASE
DROP INDEX
DROP TABLE
DROP VIEW
MERGE
RENAME TABLE