A Star Schema is a popular data modeling technique used in data warehousing. It organizes data into a star-like structure, consisting of a central fact table surrounded by multiple dimension tables.
The fact table in a star schema represents the primary focus of the data warehouse and contains quantitative measures or metrics. These measures are typically numerical values that can be aggregated, such as sales revenue or product quantity. The fact table is connected to various dimension tables through foreign key relationships.

Dimension tables in a star schema provide descriptive attributes for the data in the fact table. They contain textual or categorical data that provide context to the measures in the fact table. For example, in a sales data warehouse, dimension tables could include tables for products, customers, and time periods.

The star schema gets its name from the visual representation of the tables, where the fact table sits in the center like a star, with dimension tables radiating outwards. This structure simplifies data retrieval and analysis, as it allows for efficient querying and aggregation of data.


Here's an example to illustrate the concept:
Fact Table: Sales
----------------------------------
| Product ID | Customer ID | Date    | Sales Amount |
----------------------------------
| 1          | 101         | 2020-01 | 1000         |
| 2          | 102         | 2020-02 | 1500         |
| 1          | 103         | 2020-02 | 800          |
----------------------------------

Dimension Table: Products
-------------------------
| Product ID | Product Name |
-------------------------
| 1          | Product A    |
| 2          | Product B    |
-------------------------

Dimension Table: Customers
--------------------------
| Customer ID | Customer Name |
--------------------------
| 101         | Customer X    |
| 102         | Customer Y    |
| 103         | Customer Z    |
--------------------------

Dimension Table: Dates
----------------------
| Date     | Month | Year |
----------------------
| 2020-01  | Jan   | 2020 |
| 2020-02  | Feb   | 2020 |
----------------------

In this example, the fact table "Sales" contains sales data with measures like "Sales Amount" and is connected to dimension tables "Products", "Customers", and "Dates" through their respective foreign keys.
References:
Wikipedia - Star schema
Guru99 - Star Schema in Data Warehouse
I hope this explanation helps!