Tools are physical objects used to accomplish a task or set of tasks. Common tools include screwdrivers, pliers, saws, hammers and other hand tools. Power tools are larger tools that use electricity, such as drills, sanders and grinders. Automation tools are computers and other machines used to complete tedious and repetitive tasks. There are also tools used to measure and test, such as rulers, calipers, gauges and force testing machines. Finally, there are tools used to plan and organize, such as calendars, spreadsheets and project management software.