Answer
$0$
Work Step by Step
RECALL:
$\log_b{x} = y \longrightarrow b^y = x.$
Let $y = \log_b{1}.$
Use the rule above to obtain
$b^y=1.$
Use the rule "If $a^x=a^y$, then $x=y$" (note that $1=b^0$) to obtain
$b^y=1
\\b^y=b^0
\\y=0.$
Therefore,
$\log_b{1} = 0.$
