# Tag Info

$D$ outputs a bit $b \in \lbrace 0,1 \rbrace$. When $b = 0$, it means that $D$ is guessing that the string it has been given was drawn uniformily at random from $\lbrace 0 , 1 \rbrace^{\ell(n)}$, while when $b = 1$, it means that $D$ believes the string it has been given was produced by the PRG $G$ (or vice versa).