Cryptography
Digital Forensics
SQL Injection
Cyber security is the practice of protecting computers, networks, applications, and data from attacks, unauthorized access, and disruption.
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Build in-demand cybersecurity skills with a free course on security management, risk, access control, cryptography and incident response—ideal for career starters.
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(7)
2h55m
15 exercises
Boost your cyber security skills with a free online course on system and web protection, network defenses, and real-world attacks—study fast and earn a certificate.
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29h44m
20 exercises
Build job-ready IT security skills with a free online course: risk management, Linux, networks, incident detection, and Python—plus tips for resumes and interviews.
4.8
(19)
15h04m
18 exercises
Free CourseFoundations of Cryptography: Symmetric, Public-Key, Hashing and Signatures
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(1)
32h51m
57 exercises
Free CourseAdvanced Topics in Cryptography
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22h34m
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Free CourseCyber security
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Free CourseInformation security lessons
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7h15m
11 exercises
Free CourseIntroduction to Cybersecurity
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7h43m
6 exercises
Free CourseCyber Security Masterclass
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Free CourseCompTIA Security course
4.4
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26h11m
41 exercises
Free CourseCyber Security full course
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(9)
11h03m
Free CourseCyber security full course
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11h06m
Free CourseCyber Security
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11h30m
7 exercises
Free CourseCyber Security For Beginners
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37h48m
6 exercises
Free CourseApplied Cryptography: AES, RSA, ECC, TLS, Tor and Bitcoin
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13h20m
16 exercises
Free CourseModern Cryptography for Beginners: Encryption, Hashing, Signatures and Secure Computation
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24h07m
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Free CourseModern Applied Cryptography: AES, RSA, ECC, Hashing and Post-Quantum Basics
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37h34m
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Free CourseSQL Injection Masterclass - Web Security Academy Labs
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9h42m
17 exercises
Free CourseCyber Security CISSP Exam
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9h39m
12 exercises
Free CourseCryptography and Network Security
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14h43m
28 exercises
Understanding Zero Trust Security: A Beginner’s Guide
Learn what Zero Trust security is, the core principles behind it, and why organizations are adopting this modern approach to cybersecurity.
Ransomware Explained: How It Works and How to Protect Yourself
Learn what ransomware is, how it infects devices, and the practical steps you can take to protect your data and stay safe.
How to Spot Phishing Emails: A Practical Guide
Learn the practical warning signs of phishing emails and how to protect your accounts from online scams.
Threat Modeling for Beginners: How to Think Like an Attacker to Build Safer Systems
Learn threat modeling step by step to identify risks, prioritize threats, and design safer systems with practical cyber security habits.
Security Operations Center (SOC) Fundamentals: How Blue Teams Detect, Triage, and Respond
Learn SOC fundamentals including detection, triage, investigation, and response to build practical cyber security defense skills.
Building a Practical Cyber Security Learning Path: From First Concepts to Hands-On Defense
Learn a practical cyber security learning path from fundamentals to hands-on defense, including hardening, monitoring, and incident response.
An Introduction to Node.js: Building Fast and Efficient Backends
Discover what Node.js is, its key features, and why it’s a top choice for building fast, scalable, and efficient backend applications.
A Beginner’s Guide to Progressive Web Apps: Bridging Native and Web Experiences
Learn how Progressive Web Apps (PWAs) blend web and native features to deliver fast, secure, and offline-capable user experiences across all devices.
Web Development
Programming Languages ( Python, Ruby, Java, C )
Office Productivity (Excel, Word and More)
Artificial Intelligence and Machine Learning
App Development
Databases
Software testing
Cloud Computing and Web Servers
Robotics and Drones
Data Science and Business Intelligence
Backend development
Programming Fundamentals
Developer and IT Tools
Hardware, Operating Systems and IT Support
Computer Basics
Game development
Develop practical digital defense skills through free online courses designed for beginners, IT learners, and professionals expanding their technical knowledge. Study essential concepts such as threat identification, risk assessment, access control, network protection, vulnerability management, incident response, secure system architecture, and information security governance. The learning paths combine educational theory with applied examples, helping students understand how security principles protect computers, applications, data, and communication infrastructures.
Explore structured lessons covering malware, social engineering, authentication, security policies, penetration testing, encryption, hashing, and common web vulnerabilities. Every course is free, includes free certification, and features exercises that reinforce comprehension and support self-paced learning. These activities help learners review terminology, evaluate security scenarios, and apply defensive methodologies.
Choose introductory instruction or advance into technical subjects such as SQL injection, public-key infrastructure, AES, RSA, ECC, TLS, digital signatures, secure computation, and post-quantum fundamentals. Learners can also study security management and preparation topics related to CISSP and CompTIA Security. This flexible online education supports independent study, professional development, academic review, and foundational preparation for cybersecurity roles.
For deeper study of encryption algorithms, key management, hashing, and secure protocols, browse the related free cryptography courses. Connecting cryptographic theory with network and application security provides a broader understanding of confidentiality, integrity, authentication, and non-repudiation.
To access the courses, exercises, and free certification, users must install the Cursa app. Get it on Android through Google Play at Download for Android or install it on an iPhone through the App Store at Download for iOS / iPhone. Start learning from any location and progress through the lessons according to your schedule.
What is cyber security?
Cyber security is the practice of protecting computers, networks, applications, and data from attacks, unauthorized access, and disruption.
Which cyber security course is best for beginners?
Start with a cybersecurity fundamentals or introduction course covering threats, networking, passwords, malware, and basic security practices.
Do I need programming skills to learn cyber security?
No. Beginners can start without coding, though Python, scripting, SQL, and networking knowledge are valuable for advanced roles.
What topics are covered in a cyber security course?
Courses may cover network security, ethical hacking, penetration testing, cryptography, cloud security, incident response, and information security management.
What is the difference between cyber security and information security?
Cyber security focuses on protecting digital systems from cyber threats, while information security protects information in any format, including physical records.
Can I learn ethical hacking through online courses?
Yes. Ethical hacking and penetration testing courses teach authorized methods for finding, testing, and reporting security vulnerabilities.
Which cyber security certifications can beginners prepare for?
Beginner-friendly paths often prepare learners for CompTIA Security+ fundamentals, while advanced learners may pursue CISSP or specialized penetration testing certifications.
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What are people saying about free online courses of Cyber Security
Masooma Batool
Solve 2^X \equiv 4 \pmod{7}. Powers of 2 mod7: 2^1=2, 2^2=4, 2^3=1, 2^4=2, ... So 2^2 \equiv 4 \pmod{7}. Thus X=2.
CourseCryptography and Network Security
Akash
this app so amazing their lecture is so knowledgeable
CourseAdvanced Topics in Cryptography
Masooma Batool
53 is prime. Miller-Rabin: a=2, 2^13 mod53=30, 2^26 mod53=52≡-1. Pass.
CourseCryptography and Network Security
Masooma Batool
Multiplicative inverse of 10 mod 11? Since 10 and 11 are coprime, inverse exists.10 × x ≡ 1 mod 11 → x = 10 (becz 10×10=100 ≡ 1 mod 11) So invrs is 10
CourseCryptography and Network Security
Ayo George
it is the best resource for a beginner and a non-IT person to foray into tech. so detailed, well explained; highly robust. Thank you Google for this.
CourseIT Security
Darlene
Thank you I have a daughter Name Candis Shereece Swinney
CourseCompTIA Security course
Tami Agosto
I thought this lesson was for pc's in general. But I continued thru full lesson bc Eli the CG kept me interested bc of his delivery. TY 4 your service
CourseCyber Security
Johannes Sheriff
Am lost. The terminologies are too much.
CourseComputer systems security
Masooma Batool
X ≡ 2 mod3, 2 mod5, 1 mod11. CRT: moduli 3,5,11 coprime. M=165. Compute: (2×55×1 2×33×2 1×15×3) mod165 = (110 132 45)=287 mod165 = 122. So X=122.
CourseCryptography and Network Security
Rashid
can I get a job with only this certificate?
CourseCyber security full course