Programming tutorials

Computer Basics8 lessons · about 5 h

New to computers? Start here: what a computer is, how 0s and 1s store everything, files and folders, the internet, and thinking in steps. No coding needed, and it's all free.

1. What a computer does
2. Inside the machine
3. Zeros and ones: binary
4. Text, colours and pictures
5. Files and folders
6. How the internet works
7. Algorithms: finding fast
8. Pseudocode and bugs

Robot Quest10 lessons · about 6 h

Guide Bit the robot with real Python: walk, turn, collect gems and reach the flag.

1. First steps
2. Turning
3. Collecting gems
4. Repeat with for
5. Patterns in a loop
6. Loops inside loops
7. Look first: if
8. Keep going: while
9. New commands: def
10. Final: any maze

Python from Zero14 lessons · about 14 h

Seven stages from your first print() to your own functions, ending with a graduation challenge.

1. print() and calculations
2. Reading error messages
3. Variables
4. Types and input()
5. Indexing and slicing
6. String methods and f-strings
7. if and else
8. elif, and, or, not
9. for and range()
10. while loops
11. List basics
12. Working with lists
13. def, parameters and return
14. Graduation challenge

SQL and Databases6 lessons · about 8 h

Ask a real database questions, join tables, change data safely and design tables that stay correct.

1. SELECT and WHERE
2. Sorting and limiting
3. Grouping and counting
4. Joining tables
5. Changing data and transactions
6. Keys, constraints and indexes

Linux and the Command Line6 lessons · about 8 h

Work on a server the way engineers do: files, search, pipes, permissions, services and scripts, in a safe practice terminal.

1. Files and folders
2. Reading and searching
3. Pipes and redirection
4. Permissions and sudo
5. Processes and services
6. Shell scripts

Git and GitHub6 lessons · about 6 h

Commit, branch, merge, resolve conflicts, push and pull, the way teams work, in a safe practice repository.

1. Commits
2. Seeing and undoing changes
3. Branching and merging
4. Merge conflicts
5. Remotes: push and pull
6. .gitignore and pull requests

Frontend: HTML, CSS and JavaScript8 lessons · about 12 h

Structure a page, style and lay it out, then make it load data and react to clicks.

1. The structure of a page
2. Forms and accessibility
3. Selectors and the cascade
4. Layout: boxes, flexbox, phones
5. JavaScript basics
6. Arrays, objects and JSON
7. Async and fetch
8. State and rendering

Data Structures and Algorithms8 lessons · about 16 h

The patterns behind interview problems: complexity, two pointers, hash maps, stacks, binary search, recursion, graphs and dynamic programming, each with speed tests.

1. Big-O: counting steps
2. Two pointers and sliding windows
3. Hash maps and sets
4. Stacks and queues
5. Binary search
6. Recursion and merge sort
7. Graphs: BFS and DFS
8. Dynamic programming

Computer Networks6 lessons · about 8 h

Addresses, DNS, TCP, HTTP and the whole journey of a request, plus how to find what's broken.

1. IP addresses and subnets
2. DNS
3. TCP, UDP and ports
4. HTTP requests and responses
5. Finding what's broken
6. From URL to page

Operating Systems6 lessons · about 8 h

Scheduling, races and locks, virtual memory, caches, deadlock and file systems, each built as a small simulation you can run.

1. Processes and scheduling
2. Threads, races and locks
3. Virtual memory and paging
4. Page replacement and LRU
5. Deadlock
6. File systems

Backend Development6 lessons · about 10 h

Routing, JSON APIs, databases, login and permissions, middleware and API design, in plain Python.

1. Routing
2. JSON APIs and validation
3. Databases from code
4. Sessions, 401 and 403
5. Middleware and errors
6. API design and pagination

Software Testing5 lessons · about 7 h

Write tests that catch real bugs: edge cases, fakes, tables, properties and test-first.

1. Your first tests
2. Edge cases
3. Fakes and dependency injection
4. Tables and properties
5. TDD and regression tests

Cyber Security Basics9 lessons · about 12 h

Think like a defender: passwords, injection, tokens, logs and firewalls, each tried out in real code.

1. Threats and risk
2. Encoding and encryption
3. Hashing and salt
4. Brute force in numbers
5. SQL injection
6. XSS and path traversal
7. Tokens and HMAC
8. Finding attacks in logs
9. Firewall rules

DevOps: Containers, CI and Kubernetes5 lessons · about 10 h

Package apps with Docker, run stacks with Compose, test and deploy with GitHub Actions, and run them on Kubernetes.

1. Containers and the Dockerfile
2. Layers, caching and small images
3. Docker Compose
4. CI with GitHub Actions
5. Kubernetes basics

Cloud and Reliability5 lessons · about 8 h

Terraform, permissions, autoscaling and SLOs: build cloud infrastructure and keep it healthy.

1. Terraform basics
2. Plans and state
3. IAM and least privilege
4. Autoscaling
5. SLOs and error budgets

AI Foundations6 lessons · about 9 h

Data, regression, gradient descent, nearest neighbours, honest evaluation and retrieval, built from scratch in Python.

1. Data, features and labels
2. Linear regression and loss
3. Gradient descent
4. k-nearest neighbours
5. Measuring a model
6. Embeddings and retrieval

System Design5 lessons · about 8 h

Estimate the load, then cache, shard, rate-limit and queue: the building blocks of systems that stay up, each one coded and tested.

1. Back-of-the-envelope estimates
2. Caching
3. Load balancing and consistent hashing
4. Rate limiting
5. Queues, retries and idempotency