The term "read lengths" refers to a specific type of DNA sequencing technology that measures the length of DNA fragments being read during the process. This method is used in conjunction with other techniques such as gel electrophoresis or capillary electrophoresis, which separate and measure the size of DNA fragments based on their molecular weight. The "read lengths" refers to the amount of continuous sequence data that can be generated from a single DNA fragment during sequencing. This term is commonly used in reference to next-generation sequencing technologies where short reads are typically generated, ranging from 50 to 200 base pairs in length. The read lengths can vary depending on the specific technology and experimental conditions being used.