documentclass{article}
usepackage{pgfplots}
pgfplotsset{compat=1.15}

begin{document}

begin{figure}[ht]

centering

begin{tikzpicture}[scale=1.25,line width=1pt]
begin{axis}[
color= white,
xmin=-28.9,
xmax=28.9,
ymin=-28.9,
ymax=28.9,
axis equal image,
axis lines=middle,
]

foreach x in {-24,..., 24}
    {draw[thin, gray] (x,-24) -- (x,24);}

draw[black, thin] (-24,-24) -- (-24,24) -- (24,24) -- (24, -24) --
(-24,-24);

node[black, below] at (24,-24) {$(1,0)$};

node[black, below] at (-24,-24) {$(0,0)$};

node[black, above] at (-24,24) {$(0,1)$};

node[black, above] at (24,24) {$(1,1)$};

end{axis}
end{tikzpicture}

end{figure}

end{document}