About
Programming lessons you can trust, because every example was run first
PoolString is a free place to learn programming. It starts with a complete Core Java course, and more technologies are being written.
What makes a PoolString lesson
Every example runs
Each program in a lesson is compiled and run before it is published. If it does not run, it does not ship.
The output is real
The output under an example is what the program actually printed, never what I expected it to print.
One idea at a time
A lesson teaches one thing, in plain words, and then shows you where it fits with the rest.
Free to read
No sign-up and no paywall. Open a lesson and start reading.
What is here today
Who writes it
Naveen Anamaneni
I build software for a living, and I have been doing it for more than twelve years: telecom systems, banking risk engines, data pipelines, and lately AI platforms.
Meet Naveen →Stay in the loop
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