What tool is typically used for achieving precise lines in haircuts?

The tool that is typically used for achieving precise lines in haircuts is a straight razor or trimmer. This is due to the fact that straight razors can create very clean and sharp edges, allowing for superior control to shape and detail hairlines and other areas where precision is crucial. Similarly, trimmers are designed to provide fine detailing, especially in areas such as the nape or around the ears, contributing to a crisp and well-defined appearance.

While a pair of scissors is essential for cutting and layering hair, it may not provide the same level of precision in creating sharp lines as a razor or trimmer. A comb is primarily a guiding tool for sectioning and managing hair rather than cutting, and clippers are generally used for bulk cutting and fading rather than achieving fine, detailed lines. The combination of straight razors and trimmers aligns best with the precision required in haircutting techniques, making them the appropriate tools for that purpose.