Many publishers are temporarily providing free access to eBooks/slides/videos and other eContent during the COVID-19 crisis. I’ve arranged some of them I like. Please find below.

1. Security, Pentesing, InfoSec - Web Link
2. Exploit Development - Web Link
3. Total OSCP Guide - Web Link
4. Creating a Rootkit to Learn C - Web Link
5. The TCP/IP Guide - Web Link
6. Advanced SQL and database books and resources - Web Link
7. Syncfusion - software development, data visualization, and data science - Web Link
8. Mastering Embedded Linux - Blog Series - Web Link
9. Course materials for Modern Binary Exploitation by RPISEC - Web Link
10. OSCP Human Guide - Web Link
11. Learn Regex by Examples - Web Link
12. Mastering GNU Awk - Web Link
13. Javascript Info - Web Link
14. Malware Analysis course at University of Cincinnati, Jan 2020-Apr 2020 - Web Link
15. Teach Yourself Computer Science - Web Link
16. Deep Dive Into Modern Web Development - Web Link
17. Malware Analysis Traning - Web Link
18. Hundreds of freely accessible courses from METU - Web Link
    • Computer Engineering - Web Link
      • C Homework Collection - Very Best - Web Link
      • Data Structure - Very Best - Web Link
19. Awesome Reverse Engineering - Web Link
20. Algorithm 101 from MIT - Web Link - Exams and Solutions
21. C/C++ Books - Web Link