VBRL stands for Variable Bitrate (VBR) encoding, which is a method of compressing audio or video files where the bitrate varies depending on the complexity of the content being encoded. Unlike constant bitrate (CBR) encoding, which maintains a fixed bitrate throughout, VBR allows for higher quality in complex sections while using less data in simpler sections. This results in more efficient file sizes without compromising overall quality. VBR is commonly used in media formats like MP3 and video streaming.