Vehicle jacks are used to lift the vehicle and/or to support large components when removing or fitting them from/into a vehicle. They must always be used in accordance with the manufacturers instructions and should be inspected on a regular basis to ensure that they are in full working order. They are available in a range of configurations:
Each of these are designed for a particular application and should NEVER be used for a job for which they not recommended, for instance the small scissor jack provided with a vehicle for the purposes of changing a road wheel in a roadside flat tire situation should NEVER be used to support the vehicle that requires a person to get underneath the vehicle to complete any task.
All jacks should be regarded as a lifting tool and NOT a supporting tool, they should always be used with support of axle stands which are designed to take the weight of the vehicle when they are positioned correctly under the vehicle.
Source: CDX Global & Wikipedia - en.wikipedia.org
