Computer Science

The Wikipedia article that explain the Open Systems Interconnection (OSI) model, which is a reference model from the International Organization for Standardization (ISO).

CIDR is a notation for describing blocks of IP addresses and is used heavily in various networking configurations. This visualization helps users calculate CIDR.

This channel is for people looking to learn about Cisco networking, and networking in general.

The following index of articles all cover topics within the CCNA (Cisco Certified Network Associate) curriculum.

Black Hat is the most technical and relevant information security event series in the world. For more than 25 years, Black Hat Briefings have provided attendees with the very latest in information security research, development, and trends in a strictly vendor-neutral environment.

A channel dedicated to ethical hacking and cybersecurity.

Offers courses to become certified in cybersecurity, including some free content and at-cost courses.

Offers hands-on cybersecurity courses for free and on a per monthly basis.

This is a virtual resource for users to learn about operating systems.

A seminal book on operating systems available online for free.

A nonprofit central hub for Linux.

Free newsletter with summaries of engineering blog posts from across the internet.

A good starting point for anyone new to systems design. This goes through the core concepts of system design and includes additional reading.