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In this article, we'll explain "DeepSeek," the high-performance AI developed in China, in a way that's easy to understand even for beginners.
DeepSeek is a high-performance AI (artificial intelligence) developed by a Chinese company that you can use for free. Just like ChatGPT and Claude, it can hold conversations with people and write text.
In April 2026, the latest version, "DeepSeek-V4," was released. This new version lets you choose between two models: the smarter "Pro" model and the faster "Flash" model.
DeepSeek's biggest feature is that it's just as capable as other paid AIs, yet it's essentially free to use. It is particularly good at programming (writing instructions for computers) and solving math problems.
DeepSeek is also what's known as "open source" — an AI whose underlying code is publicly available. This gives it the advantage of being customizable (modifiable) by developers to suit their own needs.
DeepSeek can help with a wide range of tasks. Here we introduce five of its main features.
DeepSeek can automatically write programming code (instructions). Simply ask it something like "Write a program where pressing a button switches the screen," and it will generate the code immediately.
It is regarded as more accurate at programming than other AIs, making it a powerful ally for engineers.
It can write all kinds of text for you, including emails, reports, and social media posts. It is also skilled at "summarizing" — condensing long pieces of text into shorter ones.
For example, if you feed it the minutes from a long meeting, it can extract only the key points.
DeepSeek excels at mathematics and can solve complex calculations and equation problems. It boasts 90% accuracy in test results, making it useful for students and researchers alike.
It also carefully explains the steps along the way, so it can be used as a study aid.
It can read PDF and text files and find the information you need. For example, it can extract only the important terms from a contract.
It also has the capacity to process an enormous amount of information — one million tokens (approximately 750,000 words) — all at once.
By integrating with customer management systems and reservation systems, it can automatically generate replies to inquiries and handle routine tasks entirely on autopilot.
For small businesses, it can become a powerful tool for compensating for staff shortages.
Getting started with DeepSeek is very easy. Even beginners can get going in five minutes.
First, visit DeepSeek's official website. Search for "DeepSeek" in a search engine and you'll find it right away.
Register your email address to create a free account. In some cases, you may also be able to log in with a Google account or Apple ID.
In the input field at the bottom of the screen, type what you'd like done in English. For example, if you type "Write a calculator program in Python," you'll get an answer right away.
Review the text or code that DeepSeek has generated. If you're not satisfied, you can ask follow-up questions like "Can you explain in more detail?" or "Can you try a different approach?"
In addition to the web version, a smartphone app and an API (a mechanism that allows use from programs) for developers are also available.
DeepSeek has its strengths, but there are also points to be cautious about. Understand both sides before using it.
Overwhelmingly low cost: It is essentially free to use. Even the paid API version costs about one-tenth the price of ChatGPT.
High coding performance: It demonstrates greater accuracy than other AIs on programming and math problems.
Open source: Developers can customize it themselves, making it easy to integrate into their own systems.
Large context capacity: It can process one million tokens of information at once, making it convenient for analyzing large volumes of documents.
Data is sent to China: DeepSeek is operated by a Chinese company, meaning information you enter is sent to servers in China. Be careful not to input confidential information.
Slightly lower accuracy in Japanese: Since it was developed primarily around English, conversation accuracy in Japanese can be somewhat lower compared to ChatGPT or Claude.
Usage restrictions for government agencies: In some countries, including Taiwan, Australia, and the United States, use by public institutions has been prohibited due to security concerns.
DeepSeek is particularly recommended for the following types of people.
On the other hand, companies that handle highly confidential information, or those who require highly accurate text writing in Japanese, may want to consider other AI tools as well.
DeepSeek is a tool worth trying, whether you're using an AI tool for the first time or you already use other AIs. Start by trying out the free version and see if it suits your needs.
This article is a cross-post from AI Friends.
