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LLM (Large Language Model)

AI model trained on billions of words that understands and generates natural language. 2026 examples: GPT-5, Claude 4.7, Gemini 2.5 Pro.

What is an LLM

LLM stands for "Large Language Model". It's a neural network trained on vast text (books, web, code) to predict the next word in a sequence. This simple capability, scaled to billions of parameters, produces emergent abilities: question answering, creative writing, coding, reasoning, translation, analysis.

Relevant models in 2026

  • GPT-5 (OpenAI): best for voice (Realtime API), image generation, broad tool use. Price: $2.50 input / $10 output per 1M tokens.
  • Claude 4.7 Sonnet (Anthropic): best for code, long-document analysis (1M context), agentic reasoning. Price: $3 / $15.
  • Claude 4.7 Opus: max quality for complex tasks. More expensive.
  • Gemini 2.5 Pro (Google): cheap alternative, good Google Workspace integration.
  • Haiku 4.5 / GPT-5 Mini: small, cheap models for bulk processing.

What an LLM can do for business

  • Chatbot answering support, sales, FAQs
  • Voice agent handling phone calls
  • Internal assistant for documentation (HR, IT, legal)
  • Automated personalized email generation
  • Summarizing calls, meetings, contracts
  • Automatic translation (much better than classic Google Translate)
  • Sentiment analysis on reviews or feedback

What it CAN'T do

LLMs don't have real-time internet access (except via tools), don't retain info between conversations (except via artificial memory), can hallucinate (make up facts) - that's why pairing with RAG is essential for production. They're not replacements for databases or deterministic applications.

Frequently asked questions

What's the difference between GPT-5 and Claude 4.7?

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GPT-5 wins on voice and images. Claude 4.7 wins on code, long-document analysis and autonomous agents. In production we use hybrid: GPT-5 for voice/chat, Claude for documents/code.

What does it cost to use an LLM monthly?

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For a typical chatbot with 10,000 messages/month: $30-100 in API costs. Plus hosting and integrations: $200-600 total/month.

Can I run an LLM locally without internet?

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Yes, open-source models (Llama 3.3, Qwen 3) run on GPU or even CPU. Quality is below GPT-5/Claude but sufficient for non-critical cases. Hardware needed: 16-80GB VRAM.

Will LLMs replace developers?

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Not short-term. They help them be 2-5x more productive (coding with Claude/GPT). Replace repetitive jobs (simple CRUD, boilerplate), but not complex ones (architecture, deep debugging).

Related terms

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