The Optical Scan and the Punched Card.
The two most common types of trencher machines are the walk behind and the attachment models. They are used for digging trenches for laying pipe, cable or for trench warfare.
to allow for transmission on two separate LANs at the same time. Perhaps the most common application of dual Ethernet is in firewall machines.
lever and wedge
A coalition is to bring two groups together with the aim of making them to work together for the common good of the party or common objecive
There are two butterfly's that are known as the most common. The two most common butterflies are the Sulphurs and Whites butterfly.
Pashtun and Tajik are the two most common tribes.
Because they use low levels of radiation, there are some dangers to using x-ray machines. The two most common are cell damage, particularly with pregnant women and children, and genetic damage to reproductive cells.
The two most common operating systems or Windows and Mac