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learn-c.org is a free interactive C tutorial for people who want to learn C, fast.
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Learn to Code — For Free — Coding Courses for Busy People
Learn to Code — For Free
GeeksforGeeks
A Computer Science portal for geeks. It contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview Questions.
Learn Python – Free Interactive Python Tutorial
learnpython.org is a free interactive Python tutorial for people who want to learn Python, fast.
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learn-php.org is a free interactive PHP tutorial for people who want to learn PHP, fast.
