What is the difference between series battery connections and parallel battery connections and how do they increase battery capacity and voltage?

In a series connection, batteries of like voltage and amp-hour capacity are connected to increase the voltage of the overall assembly. The positive terminal of the first battery is connected to the negative terminal of the second battery and so on, until the desired voltage is reached. The final voltage is the sum of all battery voltages added together while the final amp-hours remains unchanged.

In a parallel connection, batteries of like voltages and capacities are connected to increase the capacity of the overall assembly. The positive terminals of all batteries are connected together, or to a common conductor, and all negative terminals are connected in the same manner. The final voltage remains unchanged while the capacity of the assembly is the sum of the capacities of the individual batteries of this connection.