Rohit Kumar's presentation on barcode technology covers its definition, types (1D and 2D), and functionality, emphasizing how barcodes serve as automatic identification methods by encoding data through black and white patterns. The presentation further discusses the components of barcode scanners, the working of QR codes, and the applications and benefits of barcodes in various industries, while also noting some disadvantages like system failures and damage to barcodes. Overall, barcodes are essential for efficient and accurate data collection in modern business processes.