What are transformers in AI?

AI has revolutionized numerous industries, and the AI transformer model is at the core of many groundbreaking advancements. Initially introduced in 2017 by researchers at Google in their paper Attention Is All You Need, this model architecture has become foundational for large language models (LLMs) and other generative AI systems.

From natural language processing (NLP) to image recognition and even music generation, transformer models have emerged as an essential part of deep learning. But what exactly is a transformer model, and why has it become so crucial in modern AI?

A transformer model is a neural network architecture primarily designed to process sequential data, such as text or speech. Unlike earlier neural networks like recurrent neural networks (RNNs), which handle data step-by-step, transformers process entire sequences of data simultaneously. This parallel processing allows them to handle larger datasets more efficiently and enables faster training and inference.

Transformers have become widely used as the backbone of many LLMs, including OpenAI’s GPT models and Google’s Gemini models. These models power advanced tasks like language translation, text summarization, and question-answering, making transformers indispensable in applications ranging from chatbots to recommendation systems.

According to Adam Clarke, a software engineer at Rocketmakers, “Transformers are particularly good in scenarios where data is sequential and that sequence holds meaning, which is why it’s so powerful in a language context.” This strength has propelled transformers to the forefront of AI research and development, cementing their role in various applications.

How the transformer model works

At a high level, transformer models are composed of layers that process input data in stages. Each layer has two core components: the attention mechanism (or self-attention) and a feed-forward neural network.

Attention Mechanism

The attention mechanism is central to how transformers function. It helps the model determine which parts of the input are most relevant to the task at hand. Instead of processing data one step at a time, as with RNNs, transformers simultaneously examine all parts of the input sequence for context – a process known as ‘self-attention’.

This approach allows the model to identify relationships between elements, even when they are far apart in the sequence.

For instance, in language translation, the self-attention mechanism enables the model to grasp relationships between words in both the source and target languages, improving the quality of the translation.

As Terrence Alsup, a senior data scientist at Finastra, explained to ITPro, “The attention mechanism allows transformers to better capture relationships between words separated by long amounts of text, whereas previous models such as RNNs and long short-term memory networks (LSTMs) would struggle.”

Positional Encoding

While transformers process data in parallel, they still need a way to recognize the order of the input sequence. This is where positional encoding comes into play. By adding a unique encoding to each position in the sequence, transformers maintain the order of the data, ensuring that they understand the relationships between elements such as individual words based on their positions.

Feed-Forward Layers

After the attention mechanism has processed the input, the data is passed through a feed-forward neural network, refining the information further. This process is repeated across multiple layers, with the model learning more complex data representations at each stage.

Training Transformer Models

Training a transformer model involves feeding it massive amounts of data and adjusting its internal parameters to improve accuracy. The model learns by predicting the next word or element in a sequence and comparing its predictions with the actual data. This iterative process allows the model to improve over time at tasks like text generation, translation, and summarization.

“The basic transformer model is very simple to implement using packages like PyTorch or Tensorflow,” says Alsup.

“The real challenge is training these models on a massive scale, which requires gathering and cleaning vast amounts of text data, distributing the model across multiple cores, and parallelizing training. For these reasons, most developers choose to use either a pre-trained model and finetune it if necessary or make an API call to a service such as Claude or Open AI.

Where transformers fit into AI evolution

Before transformers, recurrent neural networks (RNNs) and LSTMs were the dominant architectures for sequential data tasks. However, both RNNs and LSTMs are limited, particularly when dealing with long-range dependencies and large datasets.

RNNs process data sequentially, one step at a time, which makes them inherently slower than transformers. Additionally, RNNs struggle with remembering information over long sequences. While LSTMs were introduced to address this issue, they still have limitations when processing very long sequences.

Transformers, on the other hand, can process entire sequences in parallel, making them much faster and more efficient than RNNs or LSTMs. Their self-attention mechanism also enables them to better capture long-range dependencies in data.

While transformer models have achieved remarkable success, research is ongoing into new architectures that may surpass transformers in the future. One area of focus is improving transformer efficiency, particularly for tasks that require massive computational power. Some researchers are exploring hybrid models that combine the strengths of transformers with other architectures, while others are looking into entirely new models that may push the boundaries of what is possible in AI.

Examples of transformer models

Transformers have become the foundation for many of today’s most advanced AI models. Below are some of the most notable examples:

GPT (Generative Pre-trained Transformer)

OpenAI’s GPT models, including GPT-4, GPT-4o, and o1-preview are prime examples of transformer-based models. These models can generate coherent, human-like text and have been used in a wide range of applications, from chatbots to content creation and even programming assistance.

BERT (Bidirectional Encoder Representations from Transformers)

Developed by Google, BERT was one of the first well-known transformer models. excelled in tasks like question answering and sentiment analysis.

Google put BERT to use ranking Google Search results and improving the quality of results relative to the specific words within a user’s search term.

T5 (Text-to-Text Transfer Transformer)

Another model developed by Google, T5, treats every problem as a text-to-text task. Whether it’s translation, summarization, or classification, T5 can handle various tasks by converting them into text format. This versatility has made it a valuable tool in the NLP community.

Vision Transformers (ViTs)

While transformers were initially developed for NLP tasks, their success has also extended to computer vision. In some cases, vision Transformers (ViTs) have been applied to image recognition tasks, outperforming traditional convolutional neural networks (CNNs). By applying the self-attention mechanism to image patches, ViTs can recognize image patterns and features, making them useful for applications in fields like medical imaging and autonomous driving.

DALL·E and CLIP

Both DALL·E and CLIP are models developed by OpenAI that use transformers in creative and multimodal applications. DALL·E generates images from textual descriptions, while CLIP can understand images and text together, making it useful for tasks like image recognition, captioning, and search.

Transformer models significantly advance AI, overcoming the challenges of earlier architectures like RNNs and LSTMs. Their attention mechanism, parallel data processing, and scalability have become the foundation of today’s leading AI systems.

As transformers evolve, their influence will likely extend across industries, driving innovation in areas like customer service, content creation, and scientific research. Their transformative power is reshaping the future of AI, opening new possibilities for what machines can achieve.