LeetCode is not an AI course and I would never pretend it is one, but it belongs in this catalogue because the path to a machine learning engineering job very often runs straight through a LeetCode style coding screen, and pretending otherwise does nobody any favours. The platform is a vast, constantly updated library of algorithm and data structure problems that you solve in the browser in the language of your choice, with an online judge that checks your solution against hidden test cases the moment you submit. What makes it the industry standard is not just the size of the question bank but the quality of the surrounding material, because the discussion threads and editorials frequently explain the underlying pattern so well that you come away understanding a whole class of problems rather than memorising a single answer. The company tagging is genuinely useful when you are interviewing somewhere specific, letting you focus your time on the questions most likely to appear, and the daily problem plus weekly contests give the whole thing a rhythm that keeps you practising without having to design your own schedule.
The honest caveats matter. There is zero machine learning content here, so this is preparation for the coding round and nothing more, and you still need real AI and data study elsewhere. A lot of the most helpful features, the company filters and many of the best solutions, are locked behind Premium, and the free experience is deliberately a little frustrating to push you toward it. There is also a real risk of treating LeetCode as the goal rather than the tool, grinding hundreds of problems that have little to do with the work you will actually do, which is why I always tell people to work through a curated list like the common Blind style sets rather than starting at problem one and hoping.
My take is simple. If your target roles involve algorithm interviews, and most AI engineering roles at larger companies still do, LeetCode is the most efficient way to prepare, provided you use it deliberately and remember it is a stepping stone to the job, not the substance of it.