Conservative, or transverse, plate margins form where plates slide past each other when moving parallel to each other. This can occur both when the plates are moving in the opposite direction and when the plates are moving in the same direction at different speeds.
Conservative plate margins do not result in the creation or destruction of land as no gaps are created for magma to erupt, and neither of the moving plates are subducted into the mantle.
However, tension and friction can build between the plates, particularly if the plates become stuck. The release of this pressure causes earthquakes and can also result in one of the plates jolting forward.

An example of this can be seen at the San Andreas Fault in California, USA. Here, the fault stretches 800km between the North American and Pacific plates. Both of these plates move in a North-West direction at different speeds; the North American plate at approximately 6cm per year and the Pacific plate at approximately 10cm per year. This fault line is a large contributor to the amount of earthquakes experienced in California.