Subfields within Computer Science

Nested Circles – INCLUDING Examples

Written by Martin Ågren - April 13, 2026

Computer Science (CS)

Swedish: Datavetenskap

Computer Science (CS) is the overarching field that includes areas such as Artificial Intelligence (AI). 

Examples of Computer Science that are NOT AI:

• Example 1: Web development, where you write code to create a website or web application.

• Example 2: Programs that do NOT exhibit intelligent behavior. 

Artificial Intelligence (AI)

Artificial Intelligence (AI) is a subfield of Computer Science (CS).

Example of AI systems that are NOT ML-based:
Expert systems (rule-based systems without ML) that exhibit human-like intelligence.

Machine Learning (ML)

Machine Learning (ML) is a subfield of AI.
ML is today an important technology for developing AI.

How ML works: An “ML model” learns patterns and relationships from training data to produce output (for example classification/categorization or generation of text/image) without being explicitly programmed for every possible input.

Example of an ML-based AI model that does NOT use NN = Decision trees (neural networks are NOT used in decision trees).

Neural Network (NN)

Synonyms / abbreviations:

• Artificial neural network

• Neural network (assumed artificial)

• ANN

• NN

A neural network is an ML model that adjusts weights, the strength of connections between artificial neurons (nodes), as it learns patterns from training data.

Example of NN without DL = Simple classification, e.g. predicting customer behavior, such as whether a customer is likely to click on a specific link or not.

Deep Learning (DL)

Deep learning (DL) is a subfield of NN. DL is based on deep neural networks. "Deep" means that there are many layers of artificial neurons.

Examples of DL-based AI models that are NOT LLMs:

• Advanced classification, e.g. X-ray analysis.

• Text-to-image model (an AI model that can generate images). 

Large Language Models (LLMs)

LLMs are a type of AI model that is based on DL.

Examples of LLM-based AI tools include AI chatbots such as: ChatGPT, Gemini, Microsoft Copilot, Claude.