Hello and welcome to this Sudoku vocabulary course!

Why is it important to know the vocabulary and master the codes to improve in Sudoku?

First of all, in the following lessons on Sudoku, we will use specific terms to explain different techniques and strategies, so it is very important that you can understand them.
Finally, if you are passionate about playing and talking about Sudoku with friends, then it is important that you have the same vocabulary to communicate smoothly.

## The cells

Sudoku consists of a large grid of 81 **cells**. These cells must be filled with a number from 1 to 9. The cells are arranged in 9 rows, 9 columns and 9 boxes.

## The givens

When you start a Sudoku game, some cells already contain numbers. These numbers, which cannot be changed during the game, are called **givens**.

## The use of a legend

For your convenience, we will use a legend throughout the tutorials.

## The rows

A Sudoku grid has 9 rows that are numbered from 1 to 9, starting from the top. In the following grid, the highlighted row is row number 3.

## The columns

The grid also has 9 **columns** that are numbered from 1 to 9, from left to right.

Column 3 is the one selected here.

## The boxes

Sudoku has 81 cells as seen above, but also has 9 large cells, which are called **boxes**.

The cells are 3x3 cells, separated by thicker rows on the grid.

Here is an example of a selected cell.

## Cell numbering

To facilitate exchange and communication, each cell has a unique identifier.

This identifier includes the number of the row and the number of its column.

The cell in particular selected below is R5-C6 because it is on row R5 and column C6.

## The houses and buddy cells

A key part of learning Sudoku is understanding what houses are.

The term **House** is used when referring to a row, column or cell.

Each row, column and cell are called a **House**.

Buddy cells are cells that belong to the same house (same row, same column, same cell).

Let's take a look at R6-C4 to see what is selected here. All blues cells are part of the same house as the selected cell.