Unveiling Retrieval Augmented Generation (RAG)| Where AI Meets Human Knowledge

Kolli Koteswararao 08 Nov, 2023 • 9 min read


In our fast-paced digital world, artificial intelligence keeps surprising us with its remarkable capabilities. One of its latest breakthroughs is Retrieval Augmented Generation, affectionately known as RAG. This innovation is like a digital wizard that blends the skills of a librarian and a writer. It’s poised to change how we find and interpret information, promising a future where accessing knowledge is easier and more insightful than ever before.


Learning Objectives

  • Understand the fundamental concepts of Retrieval Augmented Generation (RAG).
  • Comprehend how RAG combines retrieval and generation AI approaches.
  • Gain insight into the inner workings of RAG, from query to response.
  • Recognize the significance of RAG in terms of efficiency and customization.
  • Discover the diverse applications of RAG in various fields.
  • Envision the future developments and impact of RAG technology.
  • Appreciate how RAG bridges the gap between vast digital knowledge and human interaction.


This article was published as a part of the Data Science Blogathon.

What is RAG?

Let’s start with the basics. RAG combines two distinct AI approaches:

Retrieval Augmented Generation
Source – Hyro


Imagine a digital library that houses all human knowledge. Retrieval AI has the uncanny ability to swiftly fetch the most relevant information in response to a query. It’s like having a personal librarian who can find the perfect book for your question.

Selection AI, which is a part of the Retrieval process, involves choosing the most relevant information from a retrieved set of documents. Here’s a code snippet illustrating this concept:

from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.metrics.pairwise import cosine_similarity

documents = [
    "Machine learning is a subset of artificial intelligence.",
    "Deep learning is a type of machine learning.",
    "Natural language processing is used in AI applications.",

# User query
query = "Tell me about machine learning."

tfidf_vectorizer = TfidfVectorizer()
tfidf_matrix = tfidf_vectorizer.fit_transform([query] + documents)

# Calculate cosine similarity between the query and documents
cosine_similarities = cosine_similarity(tfidf_matrix[0:1], tfidf_matrix[1:]).flatten()

# Sort documents by similarity score
most_similar_document = documents[cosine_similarities.argmax()]

# Print the most relevant document
print("Most Relevant Document:", most_similar_document)

This code snippet demonstrates how Selection AI works within the Retrieval process. It uses TF-IDF vectors and cosine similarity to select the most relevant document from a set based on a user query.


Conversely, generative AI can craft text eerily like a human would write. It can pen essays, construct conversational dialogues, or even generate poetic verses. Think of it as a skilled wordsmith, ready to compose text on any topic.

import torch
from transformers import GPT2LMHeadModel, GPT2Tokenizer

# Load pre-trained model and tokenizer
model_name = "gpt2"
model = GPT2LMHeadModel.from_pretrained(model_name)
tokenizer = GPT2Tokenizer.from_pretrained(model_name)

# User prompt
prompt = "Once upon a time"

# Encode the prompt to tensor
input_ids = tokenizer.encode(prompt, return_tensors="pt")

# Generate text
output = model.generate(input_ids, max_length=50, num_return_sequences=1)

generated_text = tokenizer.decode(output[0], skip_special_tokens=True)
print("Generated Text:", generated_text)

This code snippet showcases Generation AI, where a pre-trained GPT-2 model generates text based on a user’s prompt. It simulates how RAG creates human-like responses. These snippets illustrate the Selection and Generation aspects of RAG, which together contribute to crafting intelligent and context-aware responses.

Selection AI: Critical Component of Systems like RAG

Selection AI is a critical component of systems like RAG (Retrieval Augmented Generation). It helps choose the most relevant information from a retrieved set of documents. Let’s explore a real-time example of Selection AI using a simplified code snippet.

Scenario: Imagine you’re building a question-answering system that retrieves answers from a collection of documents. When a user asks a question, your Selection AI needs to find the best-matching answer from the documents.

Here’s a basic Python code snippet illustrating Selection AI in action:

from sklearn.feature_extraction.text import TfidfVectorizer
from sklearn.metrics.pairwise import cosine_similarity

# Sample documents (your knowledge base)
documents = [
    "Machine learning is a subset of artificial intelligence.",
    "Deep learning is a type of machine learning.",
    "Natural language processing is used in AI applications.",

# User query
user_query = "What is deep learning?"

# Create TF-IDF vectors for documents and the query
tfidf_vectorizer = TfidfVectorizer()
tfidf_matrix = tfidf_vectorizer.fit_transform([user_query] + documents)

# Calculate cosine similarity between the user query and documents
cosine_similarities = cosine_similarity(tfidf_matrix[0:1], tfidf_matrix[1:]).flatten()

# Sort documents by similarity score
most_similar_document_index = cosine_similarities.argmax()
most_similar_document = documents[most_similar_document_index]

# Print the most relevant document as the answer
print("User Query:", user_query)
print("Most Relevant Document:", most_similar_document)

In this example, we utilize Selection AI to answer a user’s question about deep learning. We establish a knowledge base, generate TF-IDF vectors to assess word importance, and compute cosine similarity to identify the most relevant document. The system then provides the most fitting document as the answer, showcasing the practicality of Selection AI in information retrieval.

This code snippet represents a simplified example of Selection AI. In practice, more sophisticated techniques and larger document collections are used, but the core concept remains the same: choosing the best information based on relevance to the user’s query.

Relation Between Large Language Model (LLM) and RAG

LLM, or Large Language Models, is a broader category of AI technology that includes models like GPT-3 (Generative Pre-trained Transformer 3). While LLMs share some similarities with RAG (Retrieval Augmented Generation) in terms of natural language processing and text generation, they serve different purposes. RAG specifically focuses on combining retrieval and generation AI techniques to provide context-aware responses. It excels in tasks where it needs to retrieve information from a large database and then generate coherent responses based on that retrieved data.

RAG Vs LLM | Retrieval Augmented Generation

On the other hand, LLMs like GPT-3 are primarily generative models. They can generate human-like text for various applications, including content generation, language translation, and text completion. LLMs and RAG are related because they involve language understanding and generation. Still, RAG specializes in combining these capabilities for specific tasks, while LLMs are more general-purpose language models.

Inner Working of RAG

RAG ingeniously combines these two AI superpowers. Here’s a simplified view:

  • Query: You ask a question or provide a topic. This serves as your query.
# Example Python code for creating a query in RAG
query = "What are the environmental impacts of renewable energy sources?"
result = rag.process_query(query)

This code snippet demonstrates how to formulate a query and send it to RAG for information retrieval.

  • Retrieval: RAG’s retrieval module goes to work. It searches through the vast knowledge base to find relevant documents, articles, or web pages.
# Example Python code for retrieving information in RAG
document = rag.retrieve_document(query)

The snippet illustrates how RAG retrieves information from vast knowledge sources, such as databases or documents.

  • Selection: RAG selects the most pertinent information from the retrieved documents. It’s like the librarian finding the most helpful book on the shelf.
# Example Python code for selecting relevant information in RAG
selected_info = rag.select_information(document)

The below snippet showcases how RAG selects the most relevant information from the retrieved documents.

  • Generation: Now comes the generation part. RAG takes the selected information and weaves it into a coherent, human-like response. It crafts an answer that makes sense to you.
# Example Python code for generating responses in RAG
response = rag.generate_response(selected_info)

This code snippet demonstrates how RAG generates human-like responses based on the selected information.

These code snippets provide an overview of the key steps in RAG’s inner workings, from query formulation to response generation. They help readers understand how RAG processes information and produces coherent responses during interactions.

Retrieval Augmented Generation


  • Question: You start by asking a question or providing a topic. This is your query, like asking, “What’s the weather today?”
  • Retrieved Query: RAG takes your question and looks for relevant information. It’s like going to a library and asking the librarian for a book on the topic.
  • Retrieved Texts: RAG searches through its vast knowledge base, like a librarian searching through shelves of books. It finds texts or documents related to your question.
  • Full Prompt: RAG combines your question and the retrieved information. It’s like the librarian handing you the book and saying, “This has the answer you need.”
  • GPT as Generator: RAG uses a powerful text generator, like GPT, to craft a response. It’s like having a talented writer turn the information from the book into a clear and understandable answer.
  • Response: RAG generates a response that makes sense to you. It’s as if the writer provides you with a well-written and informative reply.
  • User: Finally, you, the user, receive the response and get the answer to your question, just like you would when talking to a knowledgeable librarian

Why RAG is Important?

RAG is a transformative force for several compelling reasons:

  • Efficiency: It can provide spot-on answers with impressive speed, enhancing productivity.
  • Customization: RAG adapts its responses to suit different writing styles, making it incredibly versatile.
  • Knowledge Access: It’s your gateway to vast knowledge repositories, a boon for fields like education, research, and customer support.
  • Natural Conversations: RAG elevates AI interactions from robotic to human-like, making dialogues more engaging.
  • Content Creation: Writers and researchers can leverage RAG’s assistance for ideation and research.
  • Applications of RAG Real World Examples / Case studies

Real World Applications

RAG has found its way into various real-world applications, showcasing its transformative potential. Here are some notable examples:

  • Enhancing Search Engines: Leading search engines have integrated RAG technology to improve search results. When you enter a query, RAG helps refine your search by providing more contextually relevant results. This means you’re more likely to find what you’re looking for, even if your initial query was vague.
  • Virtual Assistants: Virtual assistants, such as chatbots and voice-activated devices, have become smarter and more conversational thanks to RAG. These assistants can provide detailed answers to a wide range of questions, making them incredibly useful in customer support and general information retrieval.
  • Educational Support: RAG has made its way into the education sector, benefiting both students and educators. It can answer students’ questions about various subjects, assist in explaining complex topics, and even generate quiz questions and explanations for teachers, streamlining the learning process.
  • Content Generation: Writers and content creators have discovered the value of RAG in generating ideas and assisting with research. It can provide topic suggestions, summarize articles, and offer relevant quotes, saving writers time and effort in the content creation process.
  • Medical Research: In the field of medical research, RAG has proven invaluable. Researchers can use RAG to search for and summarize the latest studies and findings, helping them stay up-to-date with the rapidly evolving medical literature.

Case Study Example: RAG-Enhanced Customer Support

A global e-commerce giant integrated RAG into its customer support chatbots. Customers could ask questions about products, shipping, and returns in natural language. RAG-powered chatbots provided quick answers and offered product recommendations based on customers’ preferences and past purchases. Customer satisfaction increased, leading to higher sales and retention rates.

Case study example | Retrieval Augmented Generation

These real-world examples illustrate how RAG is making a tangible impact across various domains, from search engines to healthcare and customer support. Its ability to retrieve and generate information efficiently is transforming how we access knowledge and interact with technology.


In conclusion, Retrieval Augmented Generation (RAG) represents a remarkable fusion of artificial intelligence and human knowledge. RAG acts as an information maestro, swiftly retrieving relevant data from vast archives. It selects the choicest gems from this digital treasure trove and crafts responses that sound remarkably human.

RAG’s capabilities are poised to transform the way we interact with technology. Its potential applications are boundless, from enhancing search engines to revolutionizing virtual assistants. As we journey deeper into the digital age, RAG stands as a testament to the incredible synergy of AI and human wisdom.

Embracing RAG means embracing a future where information flows effortlessly, and answers to our questions are just a conversation away. It’s not merely a tool; it’s a bridge between us and the vast realm of human knowledge, simplifying the quest for understanding in an increasingly complex world.

Retrieval Augmented Generation
Source – Neo4j

Key Takeaways

  • Retrieval Augmented Generation (RAG) combines retrieval and generation AI, functioning like a librarian and a skilled writer.
  • RAG’s inner workings involve query formulation, information retrieval, selection, and response generation.
  • RAG offers efficiency, customization, and natural conversations, making it versatile for various applications.
  • Its applications span search engines, virtual assistants, education, content creation, and medical research.
  • RAG is a bridge between AI and human knowledge, simplifying access to vast information resources.

Frequently Asked Questions

Q1. What is RAG?

A. RAG, or Retrieval Augmented Generation, is an advanced technology that combines two powerful AI capabilities: retrieval and generation. It’s like having a digital assistant that can find information quickly and respond to your questions in a way that sounds like a human wrote it.

Q2. How does RAG work?

A. RAG works in a few simple steps. First, when you ask a question or provide a topic, it forms your query. Then, it searches through a vast database of information to find relevant documents or articles. Once it has this information, it selects the most important parts and crafts a response that makes sense to you.

Q3. What are some applications of RAG?

A. RAG has many practical uses. It can make search engines smarter, help virtual assistants provide better answers, assist in education by answering student questions, aid writers in generating content ideas and even assist researchers in finding the latest studies.

Q4. Is RAG accessible to everyone?

A. RAG is a technology that can be used in various applications, but not everyone may have direct access to it. Its availability depends on how it’s implemented in specific tools or services.

Q5. What’s the future of RAG?

A. The future of RAG looks promising. It’s expected to make accessing information easier and improve interactions with AI systems. This technology has the potential to bring significant changes to various industries.

Q6. Can RAG be used for content creation?

A. Absolutely! RAG can be a helpful tool for writers and researchers. It can provide ideas and assist in researching topics, making the content creation process more efficient.

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Frequently Asked Questions

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