Technologies

Scientists create a wooden knife three times sharper than a steel blade

Wooden knife slices through well-done steak like go through butter.

I’ve been to enough fairs and foodie festivals to know the wooden knife and fork you get with your semi-hot duck fries are dismal excuses for cutlery. They’re good at moving food around a plate, but that’s really it. The plastic sometimes works a little better, but that’s not great for the planet. And then there’s the knives made from frozen human feces? Don’t get me started on how poorly those cut through meat.

The gold standard for knives is usually steel or ceramics, but in a new study, appearing in the journal Matter on Oct. 20, material scientists describe their latest creation: A «hardened wood knife» around three times sharper than a stainless steel dinner knife. It can «easily» cut through a medium-well done steak, according to Teng Li, a materials scientist at the University of Maryland and first author on the paper, and can be used and reused many times.

«In our kitchen, we have many wood pieces that we use for a very long time, like a cutting board, chopsticks, or a rolling pin,» Li said in a statement. «These knives, too, can be used many times if you resurface them, sharpen them, and perform the same regular upkeep.»

Using wood for cutlery isn’t a new idea — the foodie festivals will tell you that much — but Li’s team developed a two-step method for hardening the wood in their knives that increased the blade’s hardness 23-fold. This was achieved by ensuring the wood retained a higher level of cellulose.

Typically, wood contains only about 50% cellulose, which provides some structural integrity, and weaker molecules make up the rest. Li’s two-step process was able to remove these weaker components but retain the cellulose. Coating the wood in mineral oil helps protect its sharpness during use and washing.

Using a high-resolution microscope, Li’s team examined the wooden knife to determine why it was retaining so much strength. They discovered the two-step process the used prevented defects from creeping in. «The strength of a piece of material is very sensitive to the size and density of defects, like voids, channels, or pits,» he said in a statement.

The team didn’t stop at hardened wooden knives, either. They also developed wooden nails, showing they were as sharp as conventional steel nails.

The knife’s function is impressive, but its manufacturing process could also be important. The team writes that it could be a «renewable and low-cost alternative» with «the potential to replace plastic table utensils.»

Technologies

YouTubers Sue Amazon, Claim AI Tool Was Trained on Scraped Videos

The lawsuit alleges that Amazon bypassed YouTube protections to collect content for its generative AI video system.

A group of YouTube creators is suing Amazon, accusing the tech giant of secretly scraping their videos to train its AI video model without permission.

The proposed class action lawsuit, filed in federal court in Seattle, alleges Amazon used automated tools to download and extract data from millions of YouTube videos to build and improve its Nova Reel generative AI system — a model that can create short videos from text prompts and images.

At the center of the complaint is how that data was obtained. The plaintiffs claim that Amazon bypassed YouTube’s protections using virtual machines and rotating IP addresses to avoid detection, effectively sidestepping the platform’s safeguards against bulk downloading.

The lawsuit was brought by several creators, including Ted Entertainment (the company behind the H3 Podcast and h3h3 Productions), as well as individual YouTubers and channel operators. They argue that the alleged scraping violated copyright law and the Digital Millennium Copyright Act, and are seeking damages as well as an injunction to stop the practice.

Amazon did not respond to a request for comment.

The case lands at a pivotal moment for generative AI, as courts weigh whether training on copyrighted material qualifies as fair use and how much control creators retain once their work is used to build these systems. The disputes have often centered on written material, which has been at the center of the AI revolution for several years, while AI video generators such as OpenAI’s Sora and Google’s Veo have emerged more recently.

The lawsuit is one of dozens testing the boundaries of AI training practices, alongside high-profile cases from authors, artists and news organizations, including lawsuits against OpenAI and Meta, all circling the same unresolved question: Where does fair use end and infringement begin?

Technologies

The Galaxy Z TriFold Is Back. You Can Buy It From Samsung Soon

The $2,899 phone paused its sales in March after selling through its inventory, but Samsung is bringing it back to its online store.

Samsung’s $2,899 Galaxy Z TriFold is going back on sale on Friday, following a halt to its sales in March after the foldable phone sold through its inventory. Samsung has announced the TriFold’s return with a countdown clock on the phone’s online store page along with a Wednesday newsletter email sent to customers.

The initial pause, which Samsung said at the time was related to the TriFold being a «super-premium device in limited quantities,» happened after just three months of availability. The TriFold first went on sale in South Korea on Dec. 12 and then arrived in Samsung’s US store on Jan. 30. The TriFold sold out in the US within minutes of going on sale — which I know personally after joining my colleagues that morning in an attempt to buy it. Thankfully Senior Reporter Abrar Al-Heeti succeeded, and then reviewed the TriFold.

It’s unclear whether the Galaxy Z TriFold is now permanently returning to Samsung’s online store or if it is again on sale until its stock sells through. Given that the phone is very expensive, and unfolds to reveal a large, 10-inch display, it wouldn’t be surprising if its stock will be in limited quantities. We’ve asked a Samsung representative to clarify and will update if we hear more.

The Galaxy Z TriFold’s return also comes ahead of the summer season when we expect a slew of other foldable phones: Samsung typically refreshes its Galaxy Z Fold and Z Flip line in July or August, and Motorola has announced its first book-style Razr Fold phone will also debut during the season. And Apple’s rumored iPhone Fold (or perhaps iPhone Ultra based on latest rumors) could also be teased later this year.

Technologies

Help Us Crown the Most Loved Headphones and Earbuds of 2026

Got a pair you swear by? Take our People’s Picks survey to help us find a winner.

CNET just launched People’s Picks, a series of surveys where actual humans like you vote for the products and services you use. Starting in April, we want you to weigh in on your favorite headphones and earbuds. We’ll pick a winner based on which ones you love the most.

Why we want to hear from you

Our writers and editors test hundreds of products each year, but your real-world experience with these devices is something we can’t replicate in our labs. You’ve used these headphones at the gym, on your commute to work and on long flights, and that perspective is invaluable. Your voice helps others know about the headphones or earbuds you love, too.

«I review a lot of headphones and earbuds for CNET, and there are plenty of great models from the top brands in this survey that I rate highly. I’m always curious about what models people ultimately choose and why, so I’m excited to get your feedback and learn the results of this survey,» says David Carnoy, CNET’s executive editor and headphones expert.

With our survey, we’ll collect answers from real-world users like you. The headphones and earbuds chosen through our 3-minute survey will be featured in our People’s Picks roundup of the top picks based on your recommendation.

Make your voice heard

Whether you swear by a pair of $25 earbuds or love a pair of high-end headphones, your pick counts. The survey takes just a few minutes to complete, and after we gather enough information, we’ll tally the results and publish the winners.

Not sure what to pick? Check out our Best Headphones to revisit your favorites before voting.