The BLEU metric is a widely used measure for evaluating the quality of machine translations, providing an automated way to assess translation accuracy by comparing AI-generated translations against human-standard references. Developed by IBM researchers in 2002, it has become a cornerstone method for assessing how well a translation aligns with human judgment, calculating n-gram overlaps between candidate and reference translations focusing on precision. The metric has proven invaluable in evaluating machine translations across diverse language pairs, including technical documentation, image captioning, dialogue systems, and chatbots, where precise translation is crucial. While it may not capture every nuance of meaning or stylistic element, its versatility and reliability have established it as a foundational metric in the field. BLEU's calculation involves n-grams, sequences of consecutive words from both candidate and reference translations, with "clipped precision" preventing artificial score inflation from repeated words, and a brevity penalty ensuring translations are comprehensive. The BLEU metric has limitations, including resource-intensive calculations for large-scale systems, the need for proper AI model validation, and handling edge cases such as LLM hallucinations and domain-specific terminology. To overcome these challenges, teams can use Galileo's evaluation system, which streamlines automation, provides robust edge case handling, and integrates seamlessly into existing workflows.