Artificial Intelligence (AI) refers to computer systems designed to perform tasks that typically require human intelligence, such as visual perception, speech recognition, decision-making, and language translation. Modern AI includes machine learning, deep learning, and neural networks that enable systems to learn and improve from experience.

Traditional programming follows explicit instructions written by developers, while AI systems learn patterns from data and make decisions based on that learning. Instead of coding every rule, we train AI models with large datasets to recognize patterns and make predictions or classifications.

AI is used across industries including healthcare (diagnosis and drug discovery), finance (fraud detection and algorithmic trading), retail (recommendation systems), manufacturing (predictive maintenance), transportation (autonomous vehicles), and customer service (chatbots and virtual assistants).

AI is the broad concept of machines performing intelligent tasks. Machine Learning (ML) is a subset of AI where systems learn from data. Deep Learning is a specialized ML technique using neural networks with multiple layers that can learn increasingly abstract features from data.

Generative AI models are trained on vast amounts of text data to learn language patterns. They use transformer architectures to predict the next word in a sequence, enabling human-like text generation. These models don't 'understand' content but statistically predict plausible responses based on their training.

Key ethical issues include bias in algorithms, privacy violations, job displacement, lack of transparency in decision-making ('black box' problem), potential misuse for deepfakes or misinformation, and the long-term impact of advanced AI systems on society.