Artificial intelligence (AI) refers to the simulation of human intelligence in machines that are programmed to think, learn, and perform tasks that typically require human intelligence. These tasks include things like problem-solving, understanding natural language, recognizing patterns, making decisions, and even interacting with people.

AI can be divided into two main categories:

1. Narrow AI (Weak AI): This type of AI is designed to handle a specific task, such as voice recognition, facial recognition, or playing chess. Most of the AI systems we use today fall into this category. For example, Siri or Alexa are AI systems that focus on voice recognition and responding to queries.
2. General AI (Strong AI): This would be an AI system capable of performing any intellectual task that a human can do. It’s still a concept in development and not yet realized.

How AI is used in modern technology:

1. Healthcare: AI is used for diagnosing diseases, analyzing medical images, drug discovery, and even predicting patient outcomes. For example, AI-driven tools help radiologists detect early signs of diseases like cancer from X-rays or MRIs.
2. Autonomous Vehicles: AI is a key component in self-driving cars, where it helps in interpreting sensor data (like cameras, lidar, etc.), making real-time decisions about navigation, speed control, and collision avoidance.
3. Virtual Assistants: AI is used in digital assistants like Siri, Alexa, or Google Assistant. These systems use natural language processing (NLP) and machine learning to understand and respond to voice commands.
4. Recommendation Systems: AI powers recommendation algorithms on platforms like Netflix, Spotify, or Amazon. These systems analyze user behavior and preferences to suggest content or products.
5. Manufacturing and Automation: AI in robots and automated systems helps improve efficiency in factories, performing tasks like assembling products, quality control, or sorting materials.
6. Finance: AI is used for algorithmic trading, fraud detection, and personalized banking. It can analyze massive amounts of data to make quick, data-driven decisions.
7. Natural Language Processing (NLP): AI systems like GPT (the model you’re talking to) use NLP to understand and generate human-like text. It’s used in chatbots, translation services, and content generation.
8. Customer Service: AI-driven chatbots and virtual agents are increasingly used to handle customer inquiries, providing real-time support without the need for human intervention.
9. Entertainment and Media: AI is used for creating realistic visual effects, generating content (like music or art), and personalizing user experiences in gaming or media consumption.

AI is also a fundamental part of data analysis, enabling businesses to make predictions, optimize processes, and gain insights from large datasets.

In essence, AI is transforming industries and our daily lives by making systems smarter, more efficient, and capable of handling tasks previously thought to require human intellect.