For row 3, number 6 is only possible in cell (1,3)

For row 7, number 6 is only possible in cell (6,7)

For row 6, number 6 is only possible in cell (5,6)

For row 5, number 6 is only possible in cell (8,5)

For row 4, number 4 is only possible in cell (4,4)

For row 5, number 1 is only possible in cell (5,5)

For row 8, number 4 is only possible in cell (8,8)

For column 3, Number 7 is only possible in cell (3,8)

For column 4, Number 7 is only possible in cell (4,3)

For row 3, number 1 is only possible in cell (6,3)

For row 9, number 4 is only possible in cell (6,9)

For row 7, number 5 is only possible in cell (7,7)

For box 8, candidates for 5 are all in column 5, so you can remove candidates from other blocks.

Naked Pair for 1 and 8, can remove these as candidates from other cells.

For box 7, Number 8 is only possible in cell (2,9)

Number 2 is the only value possible in cell (2,3).

Number 4 is the only value possible in cell (2,5).

Number 9 is the only value possible in cell (2,6).

Number 5 is the only value possible in cell (2,2).

Number 3 is the only value possible in cell (6,6).

Number 9 is the only value possible in cell (6,2).

Number 5 is the only value possible in cell (6,1).

Number 9 is the only value possible in cell (5,4).

Number 1 is the only value possible in cell (2,8).

For column 4, Number 1 is only possible in cell (4,9)

For blocks 6 and 9, candidates for 8 are all in the same two columns (8 and 9)

X-Wing in rows for 3.

Number 9 is the only value possible in cell (7,8).

Number 7 is the only value possible in cell (7,9).

Number 3 is the only value possible in cell (9,9).

Number 5 is the only value possible in cell (5,9).

Number 9 is the only value possible in cell (1,9).

Number 3 is the only value possible in cell (1,1).

Number 2 is the only value possible in cell (4,1).

Number 8 is the only value possible in cell (5,1).

Number 1 is the only value possible in cell (8,1).

Number 4 is the only value possible in cell (9,1).

Number 9 is the only value possible in cell (3,1).

Number 3 is the only value possible in cell (5,2).

Number 7 is the only value possible in cell (8,2).

Number 2 is the only value possible in cell (9,2).

Number 8 is the only value possible in cell (7,2).

Number 4 is the only value possible in cell (3,2).

Number 8 is the only value possible in cell (3,3).

Number 3 is the only value possible in cell (7,3).

Number 7 is the only value possible in cell (1,4).

Number 8 is the only value possible in cell (9,4).

Number 3 is the only value possible in cell (8,4).

Number 2 is the only value possible in cell (7,5).

Number 3 is the only value possible in cell (3,5).

Number 2 is the only value possible in cell (1,6).

Number 7 is the only value possible in cell (9,6).

Number 2 is the only value possible in cell (3,7).

Number 9 is the only value possible in cell (4,7).

Number 8 is the only value possible in cell (8,7).

Number 1 is the only value possible in cell (9,7).

Number 5 is the only value possible in cell (1,8).

Number 3 is the only value possible in cell (4,8).

Number 2 is the only value possible in cell (5,8).