STR stands for "Short Tandem Repeat," which refers to a type of DNA sequence consisting of repeating units of two to six base pairs. These sequences are found in various locations throughout the genome and are highly variable among individuals, making them useful for genetic profiling and forensic analysis. In forensic science, STR analysis is commonly used in DNA fingerprinting to identify individuals based on their unique genetic makeup. By comparing specific STR markers from a sample, such as blood or hair, investigators can determine a match or exclusion, aiding in criminal investigations and paternity testing.