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Generative pre-trained transformer

~3 min read · Ch. 1 of 5
5 sections
  • On the 12th of June 2017, researchers at Google published a paper titled Attention Is All You Need. This document introduced the transformer architecture that powers all GPT models today. The new design replaced older recurrent neural network systems with an attention mechanism capable of processing entire text sequences simultaneously. That shift allowed engineers to train much larger and more sophisticated language models than ever before. Before this breakthrough, training such systems required prohibitively expensive amounts of manually labeled data. OpenAI applied this specific architecture to generative pre-training in 2018. They trained their first model on BookCorpus, a diverse collection of unlabeled text. This semi-supervised approach let the system learn patterns without human annotation for every single example.

  • OpenAI released GPT-1 on the 11th of June 2018 as the inaugural model in the series. It used 117 million parameters to generate coherent text from large datasets. Two years later, on the 14th of February 2019, they launched GPT-2 with 1.5 billion parameters. That version scaled both its parameter count and dataset size by a factor of ten compared to its predecessor. The company initially withheld the full model due to safety concerns about malicious use. On the 28th of May 2020, Microsoft unveiled Turing Natural Language Generation with 17 billion parameters. Later that same year, OpenAI introduced GPT-3 containing 175 billion parameters. This massive leap enabled few-shot learning where the model performed tasks it had never explicitly seen during training. By the 30th of November 2022, ChatGPT arrived using the GPT-3.5 architecture before transitioning to GPT-4 on the 14th of March 2023. The timeline continued through the 7th of August 2025 when GPT-5 debuted with an intelligent routing system.

  • Early versions of these models focused exclusively on generating text based on written input. Recent iterations like GPT-4o now process and generate images alongside audio files. Engineers trained some systems to handle multiple data types simultaneously rather than treating them as separate problems. Models such as o3 allocate additional computation time to analyze complex questions before producing answers. These reasoning models employ reinforcement learning to generate multi-step chains of thought for difficult domains like mathematics. The shift from pure text processing allows users to upload photos or voice recordings for analysis. A router in GPT-5 automatically selects between faster standard modes and slower reasoning modes depending on task complexity. This flexibility marks a departure from the single-modality focus of earlier releases.

  • In January 2022, OpenAI introduced InstructGPT to fine-tune base models for following specific instructions. That update improved accuracy while reducing toxic sentiment compared to raw foundation models. By November 2022, ChatGPT launched as an online interface powered by instruction-tuned language models. Human AI trainers provided conversations where they played both user and AI roles to build suitable dialogue datasets. Companies adapted these foundations into specialized tools like EinsteinGPT for sales and marketing teams. BloombergGPT serves financial professionals with access to proprietary news data. Khanmigo guides students through studies without directly providing answers during tutoring sessions. SlackGPT helps navigate discussions within the instant-messaging service. Software plugins allow third parties to interact directly with the core interface. Google Workspace offers add-ons such as GPT for Sheets and Docs to enhance spreadsheet functionality.

  • OpenAI asserted in 2023 that the term GPT should be regarded as its own brand rather than generic technology. They revised terms of service in April 2023 to prohibit other businesses from including GPT in their product names. The United States Patent and Trademark Office declined to expedite handling of OpenAI's application in April 2023. A determination followed in May 2023 stating that GPT was both descriptive and generic. Despite this setback, OpenAI continued pursuing arguments through available legal processes throughout November 2023. The European Union Intellectual Property Office registered GPT as a trademark in spring 2023 but faced challenges by spring 2024. Switzerland also granted registration in spring 2023 before similar disputes emerged globally. Media reports suggested success might rely on the fame of ChatGPT itself rather than the bare acronym. Failure to secure U.S. trademarks does not preclude common-law rights or international protections.

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Common questions

When did Google publish the paper that introduced the transformer architecture used by GPT models?

Researchers at Google published the paper titled Attention Is All You Need on the 12th of June 2017. This document introduced the transformer architecture that powers all GPT models today and replaced older recurrent neural network systems.

What were the parameter counts for OpenAI's first three major GPT releases between 2018 and 2023?

OpenAI released GPT-1 with 117 million parameters on the 11th of June 2018. They launched GPT-2 with 1.5 billion parameters on the 14th of February 2019, followed by GPT-3 containing 175 billion parameters later in 2020. ChatGPT arrived using the GPT-3.5 architecture on the 30th of November 2022 before transitioning to GPT-4 on the 14th of March 2023.

How has the Generative pre-trained transformer evolved from text-only processing to multi-modal capabilities?

Early versions of these models focused exclusively on generating text based on written input. Recent iterations like GPT-4o now process and generate images alongside audio files while models such as o3 allocate additional computation time to analyze complex questions.

Which specific companies created specialized tools using the Generative pre-trained transformer foundation after 2022?

Companies adapted these foundations into specialized tools including EinsteinGPT for sales teams, BloombergGPT for financial professionals, Khanmigo for student tutoring, and SlackGPT for instant-messaging discussions. Google Workspace offers add-ons such as GPT for Sheets and Docs to enhance spreadsheet functionality.

What legal challenges did OpenAI face regarding the trademark status of the term GPT in 2023?

The United States Patent and Trademark Office declined to expedite handling of OpenAI's application in April 2023 and stated that GPT was both descriptive and generic by May 2023. The European Union Intellectual Property Office registered GPT as a trademark in spring 2023 but faced challenges by spring 2024 while Switzerland also granted registration in spring 2023 before similar disputes emerged globally.

All sources

93 references cited across the entry

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