Resistor

The current at a given voltage can be controlled with a resistor
$R=\frac{U}{I}$
$I=\frac{U}{R}$
$U=R\cdot I$

Series

$U_1+U_2+\cdots +U_n=U_q$
$I_1=I_2=\cdots =I_n=I_q$

Parallel

$U_1=U_2=\cdots =U_n=U_q$
$I_1+I_2+\cdots +I_n=I_q$

Types