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29 October 2025 - 11 min

From Deep Learning to ChatGPT: Behind the Scenes of LLMs

Maya Tazi

Tech News

Artificial Intelligence

Data Science & Machine Learning

Over the past few years, a new technological wave has been reshaping the way we work, learn and even think: Large Language Models, or LLMs.

Behind this somewhat abstract term lie tools you may already be using without realizing it — ChatGPT, Claude, Gemini, Mistral AI and Llama, among others. These models, capable of understanding and generating text, represent a major milestone in the evolution of artificial intelligence.

LLMs are no longer limited to executing commands; they converse, translate, create, code, correct and advise. In just a few seconds, they can generate a marketing strategy, summarize a legal report or break down a complex concept.
This versatility explains why they are now becoming essential across industries — from Tech to healthcare, finance and education.

But understanding what an LLM is, how it works and, more importantly, how it can transform your career is another story entirely.
In this guide, we break it all down: how language models work, concrete use cases, the skills you need to develop and the best ways to train yourself to fully leverage them.

What Is an LLM (Large Language Model)?

An LLM is an artificial intelligence model capable of understanding, processing and generating human language.
In practical terms, it is a program trained on billions of texts — books, websites, forums and more — to learn how words follow one another and take meaning in different contexts.

💬 In other words, an LLM doesn’t think like a human, but it can predict the most likely next words in a sentence based on everything it has previously seen. This predictive mechanism is what enables it to write coherent paragraphs, answer questions or even generate code.

Let’s take a concrete example: You ask an LLM, “Explain the difference between front-end and back-end in web development.”
Within seconds, it draws on the patterns it learned from countless texts to produce a clear, structured answer adapted to your phrasing and level of understanding.

The most well-known models — GPT-4, Claude 3, Gemini, Llama 3 and Mistral — are built on an architecture called Transformer, developed by Google in 2017. This innovation revolutionized Natural Language Processing (NLP) by enabling AI systems to understand the global context of a sentence rather than interpreting each word in isolation.

Thanks to this architecture, LLMs can now maintain fluid conversations, write reports, generate ideas or even analyze emotions in text.

In short, an LLM is much more than a sophisticated chatbot:
It is a large-scale text analysis and generation technology that opens the door to a new era of interaction between humans and machines.

How LLMs Are Transforming Jobs

In just a few months, language models have begun reshaping the professional landscape.
Their ability to understand context, generate text, produce ideas and automate complex tasks is disrupting every sector, from marketing to healthcare to finance and Tech.

This is no longer a passing trend — LLMs are becoming full-fledged virtual collaborators, designed to amplify human work rather than replace it.

Marketing & Communication: Augmented Creativity

In marketing, LLMs have become true brainstorming partners.
They can:

• generate campaign ideas in seconds
• write social media posts or newsletters tailored to specific audiences
• analyze performance metrics and optimize messaging
• translate or adapt content for global markets

A marketing professional who knows how to guide an LLM (with precise, well-crafted prompts) can now create faster, with greater consistency and personalization.

👉 Working in communication or marketing?
Knowing how to collaborate effectively with an LLM can already transform the way you create.

Education & Training: Virtual Teaching Assistants

In education, LLMs help create course material, interactive quizzes and explanations adapted to each learner’s level.
Teachers use these models as pedagogical assistants capable of breaking down complex concepts or automatically correcting exercises. According to McKinsey, LLMs could automate nearly one-third of human work by the end of the decade — a shift comparable to the rise of the internet in the early 2000s.

Students use them to enrich their study sessions, write summaries or generate interview simulations.
LLMs make learning more interactive and accessible than ever.

Finance, Law & Business Operations: Efficiency First

In finance, LLMs automate report writing, market intelligence and risk analysis.
In law, they summarize legal documents and identify key clauses in seconds.
The result: experts can focus on strategy while the model handles administrative complexity.

The time savings are substantial — some tasks now take up to ten times less time than before.

Tech & Development: Engineers’ New Copilots

For developers, LLMs have become true coding assistants.
Tools like GitHub Copilot or ChatGPT can:

• suggest code in real time
• identify errors
• automatically document projects
• help understand unfamiliar programming languages

This human–machine collaboration boosts productivity and makes learning to code far smoother for beginners.

💡 If you’re thinking about starting a career in Tech, learning how to leverage LLMs can become one of your strongest career assets.

Human Resources & Team Management: Bringing Clarity to Workflows

HR teams now use LLMs to write job descriptions, analyze applications, draft feedback and even design personalized training plans.
Internally, teams rely on these tools to communicate more clearly, structure their ideas or formalize their projects.

In all these cases, one thing is clear: LLMs do not replace humans.
They amplify their capabilities.
And those who know how to use them are becoming some of the most sought-after profiles on the job market.

So the question is no longer whether LLMs will transform the workplace,
but how to prepare for it — starting now.

Why You Should Start Learning About LLMs Today

Large Language Models are no longer a futuristic promise; they’re already integrated into the tools you use every day — Google Docs, Notion, LinkedIn, Canva and many more.
Learning how to use them today means getting ahead of a professional transformation that’s already underway.

According to a 2024 McKinsey report, LLMs could automate up to 30% of office tasks by 2030 and profoundly reshape more than 900 million jobs worldwide.
Companies are now seeking professionals who can collaborate with AI rather than be overwhelmed by it.

A Universal, Must-Have Skill

Knowing how to work with an LLM is becoming a cross-functional skill — similar to mastering Excel in the 2000s or social media in the 2010s.
Whether you work in marketing, project management, design or Tech, understanding how to craft effective prompts and interpret model outputs can transform your daily workflow.

Anticipating the Transformation of Jobs

Every major technological shift brings new professions.
With LLMs, we’re seeing the rise of roles such as Prompt Engineer, AI Consultant or AI Product Manager.
But beyond new job titles, it’s the way we work that’s evolving:
we now collaborate with an intelligence that learns, suggests, corrects and assists in decision-making.

Companies need professionals who understand these tools and can integrate them intelligently.
Training now means staying ahead of the curve and taking an active role in the digital transition — rather than undergoing it passively.

A Unique Career Opportunity

The generative AI market is booming, and with it the demand for hybrid profiles: people who can speak both “human language” and “machine language.”
These skills are not yet widespread, which makes this moment particularly advantageous for specialization.

Learning how to use LLMs isn’t just about mastering a new tool.
It’s about learning to think differently, save time and create more value in a world where technology becomes a teammate.

👉 Want to understand how these models can fit into your job?
Mastering them now is the foundation for a resilient, agile and future-ready career.

How to Learn and Master LLMs

Learning to work with Large Language Models (LLMs) is a bit like learning a new language: at first everything feels abstract, but it all starts to make sense once you understand the underlying mechanisms.
The good news is that you don’t need to be an engineer to get started.
Today, several learning approaches exist depending on your goals and level.

1. Explore and Experiment on Your Own

Trying out tools like ChatGPT, Claude or Mistral AI is an excellent first step.
Ask questions, try different prompts, observe how the responses vary — it’s the best way to grasp how an LLM reasons.

But this exploration phase is often superficial: you understand what the model does, without really understanding how it works or how to leverage it to its full potential.

💡 Tip: Keep track of your most effective prompts. The art of prompt engineering relies heavily on experimentation and clarity of intent.

2. Learn Through Structured Training

To go further, guided training is the most effective path.
It teaches you how to use LLMs in real, practical contexts — through projects, case studies and mentorship from experts.

The best programs don’t just teach the basics; they teach you how to design solutions with AI, automate workflows and integrate these tools into your professional environment.

This is exactly the approach of Ironhack’s AI Consultant Bootcamp.
Learners discover:

• how LLMs and generative AI work
• how to craft precise, effective prompts
• how to use AI tools to solve real business cases
• how to showcase these new skills on the job market

🧭 The goal: to make you autonomous, confident and relevant in a field evolving at high speed.

3. Learn by Building

The key is hands-on practice.
Nothing beats actually creating something: designing a project, building an AI assistant, automating a workflow or developing a proof of concept.

Bootcamps like those at Ironhack put practice at the heart of learning.
From the very first weeks, you work on real use cases, in teams, and you learn to collaborate with the models instead of simply observing them.

Mastering LLMs also means learning to think differently:
to ask better questions, trust the technology and extract maximum value from it to move faster.

4. Surround Yourself and Stay Up to Date

AI tools evolve every month — sometimes every week.
Being part of a professional community and continuing to practice is essential to staying competitive.

One major advantage of a school like Ironhack is access to a global network of alumni and partner companies, which fosters collaboration, exchanges and professional opportunities.

👉 Whether you're switching careers, studying or already employed, learning to master LLMs today means investing in a skill that will serve you throughout your entire career.
And most importantly: it’s never too early to start.

FAQ

1. What’s the difference between an LLM and traditional AI?

An LLM (Large Language Model) is a type of artificial intelligence specialized in natural language.
Unlike traditional AI systems, which analyze numerical data or execute precise calculations, an LLM understands the meaning of words, sentences and context.
This is what enables it to write, translate, summarize and converse fluently.

2. Do I need to know how to code to use an LLM?

Not at all.
Most LLM tools today are fully accessible without technical skills — you simply need to express your request clearly, just like in a conversation.
That said, having some basic coding knowledge can be useful if you want to integrate an LLM into a website, chatbot or automation workflow.

Modern training programs, like those offered by Ironhack, teach these concepts step-by-step according to your level.

3. How long does it take to learn how to use an LLM?

It depends on your goal.
A few days are enough to understand the basics and start crafting effective prompts.
But to fully master the concepts, understand how the models work and apply them to your profession, a structured program lasting a few weeks remains the best option.

4. What jobs become accessible after LLM training?

Opportunities are growing rapidly.
Some of the most in-demand roles today include:

AI Consultant – helps companies integrate LLMs into their workflows
Prompt Engineer – expert in crafting high-impact queries
AI Product Manager – oversees products built on AI technologies
Data & ML Analyst – uses generative AI to process and interpret data

Skills related to LLMs are now considered a strong competitive advantage on the job market — across all industries.

5. How can I stay up to date in a field that evolves so quickly?

AI technologies evolve at an impressive pace, but staying informed is easier than it seems:

• Follow updates from key players in the field (OpenAI, Anthropic, Mistral AI)
• Join communities or learning groups
• Keep practicing — experimentation is the best way to solidify your skills

Ironhack’s training programs, for example, continuously adapt to integrate the latest developments in AI and LLMs, ensuring your skills remain up to date.

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