can you explain the sudoku brute force algorithm in detail please ( Not Code).

I read the algorithm in wikipedia : Sudoku algorithms - Wikipedia, the free encyclopedia

but still missing something.

In wikipedia, they said that :

" Briefly, a brute force program would solve a puzzle by placing the digit "1" in the first cell and checking if it is allowed to be there. If there are no violations (checking row, column, and box constraints) then the algorithm advances to the next cell, and places a "1" in that cell. When checking for violations, it is discovered that the "1" is not allowed, so the value is advanced to a "2". If a cell is discovered where none of the 9 digits is allowed, then the algorithm leaves that cell blank and moves back to the previous cell."

this specific part I'm not clear about..

can you please explain . .

Also if you could, please try to explain backtracking algorithm...

and finally which one best brute force or backtracking