What is a Large Language Model (LLM)? A Complete Beginner's Guide
By Dr. Kobkrit Viriyayudhakorn, CEO & Founder, iApp Technology
You've probably heard of ChatGPT, Claude, or Google's Gemini. These are all powered by something called a Large Language Model or LLM. But what exactly is an LLM? How does it work? And why should you care?
In this beginner-friendly guide, we'll explain everything you need to know about LLMs in simple terms - no PhD required!

What is a Large Language Model (LLM)?
A Large Language Model (LLM) is a type of artificial intelligence that can understand, generate, and work with human language. Think of it as a very sophisticated autocomplete system - but instead of just predicting the next word, it can write entire essays, answer complex questions, translate languages, and even write code.
Simple Analogy
Imagine you have a friend who has read every book, article, and website on the internet. When you ask them a question, they can draw from all that knowledge to give you a thoughtful answer. That's essentially what an LLM does - except it's a computer program that has "learned" from billions of text documents.
5 Key Terms You Need to Know
Before diving deeper, let's clarify some jargon that often confuses beginners:
1. Token
A token is the basic unit that LLMs use to process text. It's not exactly a word - it's more like a chunk of text.
| Text | Tokens |
|---|---|
| "Hello" | 1 token |
| "Hello world" | 2 tokens |
| "สวัสดีครับ" (Thai: Hello) | 3-4 tokens |
| "Artificial Intelligence" | 2 tokens |
Why it matters: LLM pricing is usually based on tokens. More tokens = higher cost. Thai language typically uses more tokens than English for the same meaning.
2. Parameters
Parameters are the "knowledge" stored inside an LLM. Think of them as the brain cells of the AI.
- GPT-3: 175 billion parameters
- GPT-4: ~1.7 trillion parameters
- Chinda Thai LLM: 4 billion parameters
- DeepSeek-V3: 685 billion parameters
Why it matters: More parameters generally mean better understanding and more nuanced responses, but also require more computing power.
3. Prompt
A prompt is the input you give to an LLM - your question or instruction.
Good prompt: "Explain photosynthesis to a 10-year-old in 3 sentences."
Bad prompt: "Photosynthesis?"
Why it matters: The quality of your prompt directly affects the quality of the response. This skill is called "prompt engineering."
4. Context Window
The context window is how much text an LLM can "remember" in a single conversation.
| Model | Context Window |
|---|---|
| GPT-3.5 | 4,096 tokens |
| GPT-4 | 128,000 tokens |
| Chinda Thai LLM | 40,960 tokens |
| DeepSeek-V3 | 128,000 tokens |
Why it matters: A larger context window means the AI can handle longer documents and remember more of your conversation.
5. Hallucination
Hallucination is when an LLM generates information that sounds confident but is actually false or made up.
Example:
- Question: "Who wrote the Thai novel 'The Lost Kingdom of Siam'?"
- Hallucinated answer: "It was written by Kukrit Pramoj in 1965."
- Truth: This novel doesn't exist!
Why it matters: Always verify important facts from LLM outputs, especially for critical decisions.
Why Are LLMs Important?
LLMs are transforming how we work, learn, and communicate. Here's why they matter:
1. Democratizing AI
Previously, using AI required extensive technical knowledge. Now, anyone can interact with AI through natural language.
2. Boosting Productivity
Tasks that took hours can now be done in minutes:
- Writing emails and reports
- Summarizing long documents
- Translating between languages
- Generating code
3. Breaking Language Barriers
LLMs can translate and understand multiple languages, making information more accessible globally - including Thai!
4. Enabling Innovation
From customer service chatbots to medical diagnosis assistance, LLMs are enabling new applications across every industry.
What Problems Do LLMs Solve?

Content Creation
- Writing marketing copy, blog posts, and social media content
- Generating product descriptions
- Creating educational materials
Customer Service
- 24/7 automated support chatbots
- Instant responses to common questions
- Multilingual customer support
Data Analysis
- Summarizing large documents
- Extracting insights from text data
- Sentiment analysis of customer feedback
Legal and Compliance
- Reviewing contracts
- Answering legal questions
- Explaining regulations in plain language
Code Development
- Writing and debugging code
- Explaining programming concepts
- Converting code between languages
Translation
- Real-time language translation
- Localizing content for different markets
- Maintaining context and tone across languages
How Do LLMs Work?
Let's break down the magic behind LLMs in simple terms:
Step 1: Training (Learning Phase)
The LLM reads billions of text documents from books, websites, and articles. During this process, it learns:
- Grammar and language structure
- Facts and knowledge
- Patterns in how humans communicate
- Context and relationships between concepts
Step 2: Understanding Patterns
Instead of memorizing text, the LLM learns statistical patterns. For example:
- After "The capital of Thailand is...", the word "Bangkok" is highly likely
- After "Good morning," a greeting response is expected
- Technical questions expect technical answers
Step 3: Generating Responses
When you give a prompt, the LLM:
- Converts your text into tokens
- Processes tokens through billions of parameters
- Predicts the most likely next tokens
- Generates a coherent response
The Neural Network Architecture
Modern LLMs use a technology called Transformers (introduced by Google in 2017). Key components include:
- Attention Mechanism: Helps the model focus on relevant parts of the input
- Layers: Multiple processing layers that refine understanding
- Training Data: Quality and quantity of data affects model performance
How to Use LLMs
Method 1: Chat Interfaces
The easiest way is through chat interfaces like ChatGPT, Claude, or iApp's AI services.
Method 2: API Integration
For developers, LLMs are available via APIs. Here's an example using iApp's Chinda Thai LLM:
import requests
response = requests.post(
"https://api.iapp.co.th/v3/llm/chinda-thaillm-4b/chat/completions",
headers={"apikey": "YOUR_API_KEY"},
json={
"model": "chinda-qwen3-4b",
"messages": [
{"role": "user", "content": "อธิบายเกี่ยวกับ AI ให้หน่อย"}
],
"max_tokens": 4096
}
)
print(response.json()["choices"][0]["message"]["content"])
Method 3: Local Deployment
Some open-source LLMs like Chinda can be run on your own computer for privacy and cost savings.
LLM Examples in Thai Context
Example 1: Thai Legal AI (Thanoy)
Need legal advice? iApp's Thanoy is an LLM specialized in Thai law:
User: โดนโจรตีหัว ผิดมาตราอะไรครับ
Thanoy: การถูกทำร้ายร่างกายเช่นนี้ อาจเข้าข่ายความผิดตามประมวลกฎหมายอาญา...
Thanoy has been trained on over 10,000 Thai legal articles and can answer legal questions in seconds.
Example 2: Thai Language Understanding (Chinda)
Chinda is Thailand's first open-source Thai LLM, optimized for Thai language understanding:
User: สรุปข่าวนี้ให้หน่อย: [ข้อความข่าวยาวๆ]
Chinda: ข่าวนี้พูดถึง... [สรุปกระชับ]
Example 3: Advanced Reasoning (DeepSeek-V3)
For complex tasks requiring deep reasoning:
User: Help me solve this math problem step by step...
DeepSeek: Let me think through this carefully...
[Shows detailed reasoning process]
Real-World Thai Use Case: Disaster Relief
During the 2024 Southern Thailand floods, Chinda LLM was used to automatically parse thousands of emergency requests from social media:
Input (messy social media post):
ขอความช่วยเหลือ คุณแม่ติดอยู่ในบ้าน น้ำเข้าบ้านประมาณเอว
มีโรคประจำตัวเบาหวาน โทร. 081-234-5678
Output (structured data):
{
"location": "บ้านในพื้นที่น้ำท่วม",
"situation": "น้ำท่วมระดับเอว",
"medical_condition": "โรคเบาหวาน",
"contact": "081-234-5678",
"urgency": "สูง"
}
This automation helped relief coordinators prioritize and respond faster!
iApp Technology's LLM Services
At iApp Technology, we offer several LLM solutions tailored for Thai businesses:
Chinda Thai LLM 4B
- FREE until December 31, 2025
- Optimized for Thai language
- Open-source and can run locally
- Try Chinda Demo
Thanoy Legal AI
- Specialized in Thai law
- Access to 10,000+ legal articles
- Fast 15-second responses
- Try Thanoy Demo
DeepSeek-V3.2
- 685 billion parameters
- Advanced reasoning capabilities
- Competitive pricing (~10 THB/1M input tokens)
- Try DeepSeek Demo
Getting Started with iApp LLM APIs
Step 1: Create a Free Account
Visit iapp.co.th/register to create your account.
Step 2: Get Your API Key
Go to API Key Management to generate your key.
Step 3: Make Your First API Call
curl -X POST "https://api.iapp.co.th/v3/llm/chinda-thaillm-4b/chat/completions" \
-H "apikey: YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "chinda-qwen3-4b",
"messages": [{"role": "user", "content": "สวัสดีครับ"}]
}'
Step 4: Explore More
Check out our full documentation and join our Discord community.
Summary
Large Language Models are transforming how we interact with technology. Here's what we covered:
- LLMs are AI systems that understand and generate human language
- Key terms: Tokens, Parameters, Prompts, Context Window, Hallucination
- Applications: Content creation, customer service, data analysis, legal AI, coding
- Thai solutions: Chinda (Thai LLM), Thanoy (Legal AI), DeepSeek (Advanced reasoning)
The AI revolution is here, and Thai businesses can leverage these powerful tools through iApp Technology's APIs.
Ready to Try LLMs?
Start exploring the power of Large Language Models today:
- Create Free Account - Get started in minutes
- Try Chinda Thai LLM - FREE Thai AI
- Explore All AI APIs - OCR, Speech, NLP, and more
- Contact Us - Enterprise solutions
Have questions? Join our Discord community or email us at support@iapp.co.th.
iApp Technology Co., Ltd. Thailand's Leading AI Company