The Newsela dataset was introduced by Xu et al. in their research on text simplification. It is a corpus that includes thousands of news articles professionally leveled to different reading complexities. The dataset is used for academic research in fields such as text difficulty and text simplification. It is made available to academic partners upon request. The dataset is often used as a benchmark in the field of text simplification. Please note that the Newsela dataset is different from the NELA datasets, which are collections of news articles for the study of media bias and other applications.