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From fundamentals to advanced topics — a structured learning path

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Learning English? Tap En — see the translation
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Become a guru — new courses keep coming

Interactive widgets in lessons

Theory feels dry or abstract? Move sliders, change values, tap — and each step becomes clear.

Examples of some widgets from lessons:

SELECT user_id, SUM(total_cents) AS revenue
FROM orders
GROUP BY user_id;
Sourceorders
user_idtotal_cents
424999
4212990
72100
Result
user_idrevenue
4217989
72100
0 / 80 steps
f(x) = (x−2)² + 0.6·sin(5x)-1.00.21.42.63.85.0-0.91.84.57.29.9
Learning rate
Balanced
iteration—
x0.5000
f(x)2.6091
f'(x) =-5.4034
step = −lr × f′(x)
= −0.1 × -5.4034
= 0.5403
x_new = x + step
= 0.5000 + (0.5403)
= 1.0403
|f'(x)| = 5.4034 (→ 0 at the minimum)
Press Step or Start to run gradient descent

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A full year of every course, widget, and update. No auto-renewal: after 12 months nothing is charged unless you choose to extend.

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IT Section

Programming

Go to section Programming

Computer Science

Go to section Computer Science

Software Engineering

Go to section Software Engineering

AI & Data

Go to section AI & Data

DevOps & Infrastructure

Go to section DevOps & Infrastructure

AI Instruments

Go to section AI Instruments

Exact Sciences

Go to section Exact Sciences