What is the difference between Isaiah and Deutero Isaiah?

Isaiah refers to the entire book traditionally attributed to the prophet Isaiah, which includes prophecies and messages spanning from before the Babylonian exile. Deutero-Isaiah, or Second Isaiah, specifically refers to chapters 40-55 of the book, believed by many scholars to have been written during the Babylonian exile. This section focuses on themes of comfort, hope, and the promise of restoration for the Israelites, reflecting a different historical context and theological emphasis compared to the earlier chapters.