Ten guides for the CompTIA Security+ exam, one idea per page: the CIA triad, encryption and hashing, social engineering, malware, network access control, incident response, logging and risk.
Read the study plan first, then work down the list. The Previous and Next links at the bottom of every guide follow this same order.
Study by domain weight, not chapter order. What the 90 minutes contain, and why 750 is not 83 percent.
Confidentiality, integrity and availability, the controls that serve each, and why strengthening one often weakens another.
One shared key or a public/private pair, when each is used, and why TLS quietly uses both.
Why a hash cannot be reversed, what a salt actually stops, and why a fast hash is the wrong tool for passwords.
Phishing, vishing, smishing, whaling and pretexting, separated by channel, target and technique.
Virus, worm, trojan, ransomware, rootkit and the rest, sorted by the two questions that separate them.
Port-based network access control: a device proves who it is before the network lets it in.
Preparation through lessons learned, why containment comes before eradication, and why sources disagree on the count.
What a SIEM adds to a pile of logs, false positives versus false negatives, and why clock sync is a security control.
The three formulas worked with real numbers, the four risk responses, and why a control can cost more than it saves.
Reading an explanation is not the same as producing the answer under time pressure. The free Security+ practice app draws from 500 written questions, every one with a worked explanation, and you can pick the topic you just read about. It runs offline, keeps your progress on your own device, and asks for nothing.
Want the overview first? The Security+ practice test page lists every topic the app covers.
Topic-selectable practice with worked explanations. Offline, no ads, no account.
Start practising →Looking for a different class? Java · Python · Discrete Math · Networking · Calculus, or the full guide catalog.
