Catalogue map
Every area, topic and subtopic, with how many entries exist at each level and of each kind. Pick a number to open exactly those entries.
- Tutorial
- A guided project from start to finish.
- Concept
- Explains how something works.
- How-to
- Steps to get a task done.
- Reference
- A cheat sheet to look things up.
- Fix
- An error message and how to solve it.
- Repos have no level or kind, so those columns can add up to less than All.
| Level | Kind | Type | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Class | Topic | Beg. | Int. | Adv. | Tutorial | Concept | How-to | Ref. | Fix | Articles | Scripts | Repos | All |
| 1 | Languages | 15 | 12 | 3 | 2 | 6 | 13 | 4 | 5 | 19 | 11 | 10 | 40 |
| 1.1 | Python | 9 | 6 | 1 | 1 | 3 | 7 | 2 | 3 | 11 | 5 | 5 | 21 |
| 1.1.1 | Basics | 1 | none | 1 | none | 1 | none | 1 | none | 2 | none | none | 2 |
| 1.1.2 | Environments & packages | 3 | 1 | none | 1 | 1 | 1 | none | 1 | 3 | 1 | 1 | 5 |
| 1.1.3 | Files & automation | 4 | 4 | none | 1 | 1 | 5 | 1 | none | 4 | 4 | 1 | 9 |
| 1.1.4 | Testing | 1 | 1 | none | 1 | none | 1 | none | none | 2 | none | 2 | 4 |
| 1.1.5 | Common errors | 3 | none | none | none | none | none | none | 3 | 3 | none | 1 | 4 |
| 1.2 | JavaScript | 5 | 6 | 2 | 1 | 2 | 6 | 2 | 2 | 7 | 6 | 4 | 17 |
| 1.2.1 | Basics | 4 | none | none | none | 1 | none | 2 | 1 | 4 | none | none | 4 |
| 1.2.2 | Async code | none | 2 | 2 | none | 1 | 3 | none | none | 1 | 3 | 1 | 5 |
| 1.2.3 | Patterns | none | 1 | none | none | none | 1 | none | none | none | 1 | 1 | 2 |
| 1.2.4 | Node.js | 1 | 3 | none | 1 | none | 2 | none | 1 | 2 | 2 | 2 | 6 |
| 1.2.5 | Common errors | 1 | 1 | none | none | none | none | none | 2 | 2 | none | none | 2 |
| 1.3 | TypeScript | 1 | none | none | none | 1 | none | none | none | 1 | none | 1 | 2 |
| 1.3.1 | Basics | 1 | none | none | none | 1 | none | none | none | 1 | none | 1 | 2 |
| 1.4 | Regular expressions | 1 | none | none | none | none | none | 1 | none | 1 | none | none | 1 |
| 1.4.1 | Basics | 1 | none | none | none | none | none | 1 | none | 1 | none | none | 1 |
| 2 | Version control | 8 | 6 | 1 | 2 | 3 | 5 | 2 | 3 | 12 | 3 | 4 | 19 |
| 2.1 | Git | 5 | 5 | 1 | 1 | 3 | 3 | 1 | 3 | 9 | 2 | 1 | 12 |
| 2.1.1 | Setup | 3 | none | none | 1 | 1 | 1 | none | none | 2 | 1 | none | 3 |
| 2.1.2 | Branching & rebasing | 1 | 2 | none | 1 | 1 | none | none | 1 | 3 | none | none | 3 |
| 2.1.3 | Undoing changes | none | 1 | none | none | 1 | none | none | none | 1 | none | none | 1 |
| 2.1.4 | Finding bugs | none | none | 1 | none | none | 1 | none | none | 1 | none | none | 1 |
| 2.1.5 | Housekeeping | 1 | 1 | none | none | 1 | 1 | none | none | 1 | 1 | 1 | 3 |
| 2.1.6 | Reading history | none | none | 1 | none | none | 1 | none | none | 1 | none | none | 1 |
| 2.1.7 | Common errors | 1 | 2 | none | none | none | none | none | 3 | 3 | none | none | 3 |
| 2.2 | GitHub & collaboration | 3 | 1 | none | 2 | none | 2 | none | none | 4 | none | 1 | 5 |
| 2.2.1 | Pull requests | 2 | none | none | 1 | none | 1 | none | none | 2 | none | 1 | 3 |
| 2.2.2 | GitHub Actions | 1 | 1 | none | 1 | none | 1 | none | none | 2 | none | none | 2 |
| 2.3 | Git tools | 1 | none | none | none | none | none | 1 | none | none | 1 | 4 | 5 |
| 3 | Shell & command line | 6 | 10 | 2 | 2 | 3 | 6 | 4 | 3 | 10 | 8 | 5 | 23 |
| 3.1 | Shell & Linux | 5 | 6 | 1 | 1 | 3 | 4 | 3 | 1 | 6 | 6 | none | 12 |
| 3.1.1 | Basics | 4 | none | none | none | 3 | none | 1 | none | 4 | none | none | 4 |
| 3.1.2 | Finding files & text | 1 | 1 | none | none | none | 2 | none | none | 1 | 1 | none | 2 |
| 3.1.3 | Text processing | 2 | 1 | none | none | 1 | 2 | none | none | 2 | 1 | none | 3 |
| 3.1.4 | Shell scripting | none | 5 | 1 | 1 | none | 2 | 2 | 1 | 1 | 5 | none | 6 |
| 3.1.5 | Backups & syncing | none | none | 1 | none | none | 1 | none | none | none | 1 | none | 1 |
| 3.1.6 | Processes & ports | none | 1 | none | none | none | none | none | 1 | none | 1 | none | 1 |
| 3.2 | Command-line tools | 1 | 1 | none | none | none | none | 2 | none | 1 | 1 | 5 | 7 |
| 3.3 | SSH & servers | 1 | 3 | 1 | 1 | none | 2 | none | 2 | 4 | 1 | none | 5 |
| 3.3.1 | Keys & config | 1 | 2 | 1 | 1 | none | 2 | none | 1 | 3 | 1 | none | 4 |
| 4 | Systems & infrastructure | 28 | 54 | 16 | 11 | 21 | 38 | 14 | 14 | 85 | 13 | 15 | 113 |
| 4.1 | Linux administration | 7 | 13 | 2 | 3 | 4 | 9 | 4 | 2 | 19 | 3 | 2 | 24 |
| 4.1.1 | Services & systemd | 1 | 6 | none | 2 | 1 | 2 | 1 | 1 | 6 | 1 | 1 | 8 |
| 4.1.2 | Disks, LVM & filesystems | 1 | 4 | 1 | none | 2 | 2 | 1 | 1 | 4 | 2 | none | 6 |
| 4.1.3 | Networking & firewalls | 2 | 4 | none | 1 | none | 3 | 1 | 1 | 6 | none | 1 | 7 |
| 4.1.4 | Packages & updates | 3 | none | none | 1 | none | 1 | 1 | none | 3 | none | none | 3 |
| 4.1.5 | Users, sudo & hardening | 2 | none | 1 | 1 | 1 | 1 | none | none | 2 | 1 | none | 3 |
| 4.2 | Containers | 1 | 2 | none | 1 | 1 | 1 | none | none | 3 | none | none | 3 |
| 4.2.1 | Docker basics | 1 | 2 | none | 1 | 1 | 1 | none | none | 3 | none | none | 3 |
| 4.2.2 | Docker Compose | none | 2 | none | 1 | none | 1 | none | none | 2 | none | none | 2 |
| 4.3 | Proxmox VE | 5 | 8 | 3 | 1 | 3 | 7 | 2 | 3 | 14 | 2 | 2 | 18 |
| 4.3.1 | Installation & first steps | 3 | 1 | none | 1 | 1 | 2 | none | none | 4 | none | 1 | 5 |
| 4.3.2 | VMs & containers | 3 | 4 | 1 | 1 | none | 3 | 2 | 2 | 7 | 1 | 1 | 9 |
| 4.3.3 | Storage | none | 1 | none | none | 1 | none | none | none | 1 | none | none | 1 |
| 4.3.4 | Clusters & high availability | none | 1 | 3 | none | 1 | 1 | 1 | 1 | 4 | none | none | 4 |
| 4.3.5 | Backup & restore | 2 | 2 | none | 1 | none | 2 | none | 1 | 3 | 1 | none | 4 |
| 4.4 | Oracle Private Cloud Appliance | 2 | 5 | 1 | none | 3 | 4 | 1 | none | 8 | none | 1 | 9 |
| 4.4.1 | Architecture & concepts | 2 | none | none | none | 2 | none | none | none | 2 | none | none | 2 |
| 4.4.2 | Compute, networking & storage | 1 | 4 | none | none | 1 | 4 | none | none | 5 | none | 1 | 6 |
| 4.4.3 | Administration & monitoring | none | 1 | 1 | none | 1 | none | 1 | none | 2 | none | none | 2 |
| 4.5 | KVM & libvirt | 3 | 5 | 1 | 1 | 2 | 3 | 2 | 1 | 8 | 1 | 2 | 11 |
| 4.5.1 | Basics | 3 | 5 | 1 | 1 | 2 | 3 | 2 | 1 | 8 | 1 | 2 | 11 |
| 4.6 | Kubernetes | 6 | 11 | 3 | 2 | 5 | 7 | 2 | 4 | 18 | 2 | 3 | 23 |
| 4.6.1 | Concepts | 5 | none | 1 | 1 | 3 | 1 | 1 | none | 6 | none | 1 | 7 |
| 4.6.2 | Workloads & services | 3 | 1 | 2 | 1 | 1 | 2 | none | 2 | 6 | none | none | 6 |
| 4.6.3 | Config, secrets & storage | none | 3 | 1 | none | 1 | 3 | none | none | 4 | none | none | 4 |
| 4.6.4 | Ingress & networking | 1 | 2 | none | none | 1 | 2 | none | none | 3 | none | none | 3 |
| 4.6.5 | Troubleshooting | 1 | 4 | 2 | none | none | 1 | 2 | 4 | 5 | 2 | 1 | 8 |
| 4.6.6 | Helm | none | 2 | none | 1 | none | 1 | none | none | 2 | none | 1 | 3 |
| 4.7 | OpenShift & OKD | 3 | 8 | 3 | 1 | 3 | 6 | 2 | 2 | 12 | 2 | 2 | 16 |
| 4.7.1 | Concepts | 2 | 2 | 1 | 1 | 3 | 1 | none | none | 5 | none | 1 | 6 |
| 4.7.2 | Deploying applications | 2 | 6 | none | 1 | none | 6 | 1 | none | 7 | 1 | 1 | 9 |
| 4.7.3 | Cluster administration | none | 2 | 2 | none | 2 | none | 1 | 1 | 3 | 1 | 1 | 5 |
| 4.7.4 | Troubleshooting | none | 3 | 2 | none | none | 1 | 2 | 2 | 3 | 2 | none | 5 |
| 4.8 | Automation & infrastructure as code | 4 | 5 | 3 | 2 | 2 | 5 | 1 | 2 | 9 | 3 | 2 | 14 |
| 4.8.1 | Ansible | 2 | 4 | 1 | 1 | 1 | 3 | 1 | 1 | 5 | 2 | 1 | 8 |
| 4.8.2 | Terraform | 2 | 1 | 2 | 1 | 1 | 2 | none | 1 | 4 | 1 | 1 | 6 |
| 4.9 | Monitoring & logging | none | 4 | none | 1 | 1 | 1 | 1 | none | 4 | none | 2 | 6 |
| 4.9.1 | Prometheus & Grafana | none | 3 | none | 1 | 1 | 1 | none | none | 3 | none | 2 | 5 |
| 4.9.2 | Logs | none | 1 | none | none | none | none | 1 | none | 1 | none | none | 1 |
| 5 | Data | 19 | 29 | 10 | 5 | 13 | 21 | 8 | 11 | 46 | 12 | 12 | 70 |
| 5.1 | SQL | 4 | 3 | 1 | 1 | 3 | 1 | 2 | 1 | 7 | 1 | 2 | 10 |
| 5.1.1 | Queries | 4 | 2 | none | 1 | 1 | 1 | 2 | 1 | 5 | 1 | 2 | 8 |
| 5.1.2 | Joins | 2 | 1 | none | 1 | 1 | none | 1 | none | 2 | 1 | none | 3 |
| 5.1.3 | Indexes & performance | none | none | 1 | none | 1 | none | none | none | 1 | none | none | 1 |
| 5.2 | CSV & JSON | 4 | 1 | none | none | 1 | 2 | 1 | 1 | 2 | 3 | 1 | 6 |
| 5.2.1 | jq & JSON on the command line | none | 1 | none | none | none | none | 1 | none | none | 1 | 1 | 2 |
| 5.3 | Data analysis | none | 1 | none | none | none | 1 | none | none | 1 | none | 2 | 3 |
| 5.4 | PostgreSQL | 4 | 9 | 3 | 2 | 3 | 6 | 2 | 3 | 13 | 3 | 2 | 18 |
| 5.4.1 | Install & connect | 3 | 3 | none | 1 | 1 | 1 | 1 | 2 | 6 | none | 1 | 7 |
| 5.4.2 | Roles & administration | 1 | 5 | none | 1 | 1 | 1 | 2 | 1 | 5 | 1 | none | 6 |
| 5.4.3 | Backup & restore | 1 | 2 | 1 | 1 | 1 | 2 | none | none | 3 | 1 | 1 | 5 |
| 5.4.4 | Performance & tuning | none | 2 | none | none | 1 | none | 1 | none | 1 | 1 | none | 2 |
| 5.4.5 | Replication & high availability | none | none | 3 | none | 1 | 2 | none | none | 2 | 1 | none | 3 |
| 5.5 | MySQL & MariaDB | 3 | 2 | 3 | 1 | 2 | 3 | 1 | 1 | 7 | 1 | 2 | 10 |
| 5.5.1 | Administration | 3 | 1 | 2 | 1 | none | 3 | 1 | 1 | 5 | 1 | none | 6 |
| 5.5.2 | Backup & restore | none | 1 | 1 | none | 1 | 1 | none | none | 1 | 1 | none | 2 |
| 5.5.3 | Replication | none | none | 3 | 1 | 1 | 1 | none | none | 3 | none | none | 3 |
| 5.6 | Oracle Database | 1 | 5 | 1 | none | 1 | 3 | 1 | 2 | 5 | 2 | 1 | 8 |
| 5.6.1 | Concepts & tools | 1 | 2 | none | none | 1 | none | 1 | 1 | 3 | none | 1 | 4 |
| 5.6.2 | Administration | none | 5 | 1 | none | none | 3 | 1 | 2 | 4 | 2 | none | 6 |
| 5.6.3 | Backup with RMAN | none | 1 | 1 | none | none | 2 | none | none | 1 | 1 | none | 2 |
| 5.7 | MongoDB | 2 | 3 | none | none | 1 | 2 | 1 | 1 | 4 | 1 | 1 | 6 |
| 5.7.1 | Basics | 2 | 1 | none | none | 1 | none | 1 | 1 | 3 | none | none | 3 |
| 5.7.2 | Administration | none | 3 | none | none | none | 2 | none | 1 | 2 | 1 | 1 | 4 |
| 5.8 | Redis | 1 | 4 | 1 | 1 | 1 | 1 | 1 | 2 | 5 | 1 | 2 | 8 |
| 5.8.1 | Basics | 1 | 2 | none | 1 | none | 1 | 1 | none | 2 | 1 | none | 3 |
| 5.8.2 | Administration & persistence | none | 4 | 1 | 1 | 1 | 1 | none | 2 | 4 | 1 | 2 | 7 |
| 5.9 | Database operations | 4 | 10 | 2 | none | 4 | 7 | none | 5 | 14 | 2 | none | 16 |
| 5.9.1 | Choosing a database | 2 | 1 | none | none | 3 | none | none | none | 3 | none | none | 3 |
| 5.9.2 | Security & access | 2 | 8 | 2 | none | 1 | 6 | none | 5 | 11 | 1 | none | 12 |
| 6 | Web | 3 | 5 | 1 | 1 | 2 | 4 | 1 | 1 | 5 | 4 | 7 | 16 |
| 6.1 | HTTP & APIs | 3 | 5 | 1 | 1 | 2 | 4 | 1 | 1 | 5 | 4 | 3 | 12 |
| 6.1.1 | Making requests | 2 | 3 | 1 | 1 | 1 | 4 | none | none | 2 | 4 | 3 | 9 |
| 6.1.2 | Status codes | 1 | 2 | none | 1 | none | none | 1 | 1 | 3 | none | none | 3 |
| 6.1.3 | Authentication | 1 | 1 | none | none | 1 | 1 | none | none | 1 | 1 | none | 2 |
| 6.2 | CSS | none | none | none | none | none | none | none | none | none | none | 1 | 1 |
| 6.2.1 | Layout | none | none | none | none | none | none | none | none | none | none | 1 | 1 |
| 6.2.2 | Selectors & specificity nothing yet | none | none | none | none | none | none | none | none | none | none | none | none |
| 6.3 | HTML & accessibility nothing yet | none | none | none | none | none | none | none | none | none | none | none | none |
| 6.3.1 | Accessibility nothing yet | none | none | none | none | none | none | none | none | none | none | none | none |
| 6.4 | Web frameworks | none | 1 | none | none | none | none | none | 1 | 1 | none | 3 | 4 |
| 6.5 | References | 1 | none | none | none | none | none | 1 | none | 1 | none | 1 | 2 |
| Whole catalogue | 75 | 105 | 31 | 18 | 48 | 79 | 31 | 35 | 169 | 42 | 48 | 259 | |
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