Hacker News is a news website focusing on computer science and entrepreneurship. It has a straightforward design and easily allows you to publish your links. Handy is the Show HN tag that you can use to showcase your project or browse other people's ones.
Smashing Magazine is an excellent web site focused on resources for web developers and web designers. That is what makes them different from some other pages. While anyone can apply to write, content is required to be in that specific domain.
CSS-Tricks is a page similar to Smashing Magazine. It is a place that contains articles on web development and web design with a bit more focus on design. If you are interested in doing something with CSS, this is a place to find it. Still, it is the most popular resource for understanding flexbox.
The Practical Dev is another place similar to CSS-Tricks and Smashing Magazine but focuses more on development. What also makes it different from the two above is that anyone can register and start writing, and essential for me as a dev, great integration with GitHub. Maybe the only downside for writing, it is done in a markup language, like the one you would use in your README files.
Once again, similar to The Practical Dev and others, but much broader topics. You can find many useful tech resources, but there are also many from other topics. The excellent part is publications, which is space focused around a common theme. One of them would be towards data science.
Twitter is one place that you should not underestimate. By following the right hashtags, you can easily see what is becoming popular, what people are talking about, and even get someone's help in your career.
If you only want to keep up to date with news on the latest gadgets, startups, and tech business news, you can use any of the sites above.