Meet DeepSeek — what it is and who makes it

The concept

DeepSeek is a reasoning-focused models served cheaply and published openly made by DeepSeek. The models behind it are the DeepSeek chat and reasoning models, with open weights for the core ones. None of that matters on its own — what matters is that you know what kind of worker you have hired. At showing its working on a problem with steps — arithmetic, logic, a small proof, a data question is the job you hand it. At being available and predictable: it is a smaller service than the frontier providers, and capacity shows is the job you keep.

Most people come to a course like this expecting a list of magic words. There is no such list. What there is, is a tool that produces an answer preceded by visible reasoning, which is either the most useful thing you will read today or a distraction, and produces it at a speed no human matches — which means the skill is not in writing the prompt, it is in knowing what a good answer looks like so you can tell the difference.

Here is the first thing to try, worded the way you will word things for the rest of the course:

Read the answer twice. The first read is for the content; the second is for the shape — did it answer the question you asked, or the question it found easiest? That second read is the habit this whole course is built on.

A college has 1,240 students. 55% are in engineering, of which one fifth are in computer science. How many computer science students are there? Show every step, state your assumptions, and mark the answer clearly.