Elementary Charge

$\textit{Elementary Charge}$, usually denoted as $e$, is the electric charge carried by a single proton, or equivalently, the negation (opposite) of the electric charge carried by a single electron. This elementary charge is a fundamental physical constant. To avoid confusion over its sign, e is sometimes called the elementary positive charge. This charge has a measured value of approximately $1.602176634 \times 10^{-19} coulombs$. In the cgs system, $e$ is $4.80320471257026372 \times 10^{-10} statcoulombs$.