
programming
useful sites that give you programming problems to solve
A fun social platform for hackers to solve interesting puzzles, build quick hacks, code game bots and collaborate to solve real-world challenges.
Free Code Camp's open source community help you build a job-worthy portfolio of real apps used by real people, while helping nonprofits.
Our 1 600 hour full stack JavaScript curriculum is completely self-paced, browser-based, and free.
We serve people who are traditionally underserved in the coding community: 80% of our students are 25 or older, and nearly a fifth are women.
Codecademy is the easiest way to learn how to code. It's interactive, fun, and you can do it with your friends.
Achieve code mastery through challenge. Improve your skills by training with others on real code challenges
Kata
In our dojo, kata are real code challenges focused on improving skill and technique. Some train programming fundamentals, while others focus on complex problem solving. Each kata is crafted for and by the community.
Kyu/Dan Ranks
Each kata on the site is set to a Kyu/Dan rank, based on its subject area and difficulty. The community collectively determines rank in the Beta Process.
Earning Ranks
You can advance through the ranks by completing kata at or above your rank - the harder the kata the faster you advance.
Honor
Honor represents the level of respect a user has earned from the community, based on their skill and contributions. Honor is earned fastest through creating kata, crafting great solutions, and constructive comments.
Are you a code newbie?
Learning to program is exhilarating and challenging... and also frustrating, exhausting, and overwhelming.
Exercism provides countless small wins. The exercises are achievable mini-quests: small and well-defined, and with enough complexity to uncover bite-sized knowledge gaps.
The solutions you write provide reviewers with clues about what you haven't grasped yet. The feedback you receive will guide you to relevant study topics and dramatically increase the ease with which you write code.
Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.
The motivation for starting Project Euler, and its continuation, is to provide a platform for the inquiring mind to delve into unfamiliar areas and learn new concepts in a fun and recreational context