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Tables in SQL are the core structure for storing data in a relational database. Think of them as spreadsheets with rows and columns, where each column has a specific data type (e.g., INT, VARCHAR) and each row represents a record. For example, a table named users might store names and ages, like "John, 25". Tables organize data efficiently, allowing you to query, update, or delete it using SQL commands.

To create a table in SQL, you use the CREATE TABLE command, defining columns and their data types. Let’s create a users table as an example:
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Run this in a database tool like MySQL Workbench or phpMyAdmin to create the table. Here, id auto-increments, name holds up to 50 characters, and age stores integers.

To add data, use the INSERT INTO command. Let’s add a user to the users table:
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Execute this to insert a record. The id auto-increments (e.g., 1), and 'John Doe', 25 is added as a row.

To retrieve data, use the SELECT command. Here’s how to fetch all users:
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Run this to see all rows, like id: 1, name: 'John Doe', age: 25. Use conditions (e.g., WHERE age > 20) for specific data.

To change a table, use ALTER TABLE. Let’s add an email column to users:
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Execute this to add the email column. Now, users can store emails up to 100 characters, enhancing its structure.