Most blue-collar jobs are considered manual labor, like track switch repairmen, machinists and petroleum pump system operators. As the name suggests, manual labor describes jobs where most of the responsibilities involve physical tasks as opposed to working on a computer.
Manual labor jobs are mostly unskilled positions, but there are exceptions. Despite being unskilled, many manual labor jobs pay well due to the level or risk involved or the environment a worker must live in. Jobs in the petroleum field, for example, are often manual labor jobs. These jobs can be dangerous, and workers often have to live on remote sites while on the job, which is why they are generally high paying positions.