Sudoku Plus consists of a 9x9 **grid** of smaller squares called **cell**s. As shown in the illustration above, each **row**, **column**, and **box** in the grid contains 9 cells. Every cell in the grid belongs to exactly one row, column, and box, which together make up the cell’s **area**. Each cell’s area contains 21 cells: the cell itself, and its 20 **peers**.

When a Sudoku Plus **puzzle** is solved, each cell is filled with one of nine **values** that comprise a value **set**. No row, column, or box can have the same value in more than one cell. This also means that no cell can have the same value as any of its peers. At the start of a **game**, typically 20 to 30 of the cells are prefilled with values. These values are **clue**s, also known as givens.

The goal is to use logic, not guessing, to **pick** the correct value for each empty cell. Each clue or pick helps in determining the proper picks for the remaining cells. Use the process of elimination to determine the proper pick. For example, if a cell’s peers are already filled with eight of the nine values in the set, the pick for the cell must be the remaining value. To help with puzzle solving, enter a **note,** or every unused value, in a cell. Once the pick has been entered into a cell, that value should be removed from the notes of all peers.