Logic Gates

\usepackage{circuitikz}

\begin{circuitikz}
  \draw (0,0) node[and port] (and) {};
  \draw (3,0) node[or port] (or) {};
  \draw (6,0) node[not port] (not) {};
  \draw (and.in 1) -- ++(-0.5,0) node[left]{A};
  \draw (and.in 2) -- ++(-0.5,0) node[left]{B};
  \draw (and.out) -- (or.in 1);
  \draw (or.in 2) -- (or.in 2 |- and.in 2) -- (and.in 2);
  \draw (or.out) -- (not.in);
  \draw (not.out) -- ++(0.5,0) node[right]{Y};
\end{circuitikz}