Fundamentals

Machine Learning

Machine learning (ML) is a branch of artificial intelligence where systems learn to improve their performance on tasks from experience (data) without being explicitly programmed with rules. Instead of hand-coded instructions, ML algorithms find patterns in training data and build statistical models used to make predictions or decisions on new data.

How Machine Learning Works

ML systems work by: (1) collecting and preparing training data; (2) choosing an algorithm (decision tree, neural network, linear regression, etc.); (3) training the model by optimising its parameters on the data; (4) evaluating performance on held-out test data; and (5) deploying the model to make predictions. The three main paradigms are supervised learning (labelled data), unsupervised learning (unlabelled data), and reinforcement learning (reward signals).

Key Use Cases

  • Email spam filtering
  • Product recommendations (Netflix, Amazon)
  • Credit scoring and fraud detection
  • Medical diagnosis support
  • Natural language understanding
  • Demand forecasting
  • Predictive maintenance

Frequently Asked Questions

What is machine learning?
Machine learning is a method of AI development where algorithms learn patterns from data rather than following explicitly programmed rules. A spam filter that learns from examples of spam and non-spam emails is a classic example.
What is the difference between AI and machine learning?
AI is the broad concept of creating intelligent machines. Machine learning is one approach to achieving AI, using statistical algorithms that learn from data. Not all AI uses machine learning — early AI used symbolic rules and expert systems.
How long does it take to learn machine learning?
With a programming background, foundational ML concepts can be learned in 3-6 months. Becoming proficient in applied ML typically takes 1-2 years. Deep expertise in cutting-edge ML research takes many years of study and practice.