GPT-3.5 Turbo Instruct, developed by OpenAI, is a language model designed for efficiently following specific instructions, distinguishing itself from the conversational GPT-3.5-turbo by focusing on task-oriented interactions rather than chat-based ones. This model aims to reduce issues like hallucinations and harmful content generation by using Reinforcement Learning from Human Feedback (RLHF), which aligns its responses more closely with user instructions and expectations. It maintains the same cost and performance as other GPT-3.5 models and operates within a 4K context window, using training data up to September 2021. Notably, GPT-3.5 Turbo Instruct has demonstrated impressive capabilities in chess, achieving an Elo rating of around 1800, which is a significant leap for GPT models that were not previously known for their chess-playing abilities. The launch of this model coincides with the phasing out of older models such as text-ada-001 and text-curie-001, set to be retired by January 4, 2024.