Additionally, NBCUniversal, which is owned by Comcast, is preparing to make an investment of about $200 million in BuzzFeed, the digital media hub known for its trending quizzes, shareable lists and push into journalism, according to two other executives who also spoke on the condition of anonymity. Mr. Bankoff said that both Vox and NBCUniversal had much to learn from each other. He said his company had developed expertise in creating strong digital brands that resonate with millennial audiences, as well as new advertising formats. Vox can tap NBCUniversal's experience in building audiences and creating short-form and long-form videos, he said.

At Vox, which had 54 million unique visitors in the United States in June, about 41 percent of the audience is 18 to 34 years old, according to the measurement firm comScore. Vox declined to disclose its revenue or profit figures.

Mr. Bankoff said he was not prepared to specifically say how the two companies would collaborate, but he noted that they could cross-promote each other's brands, create new premium advertising products and leverage new digital publishing technologies. He also said Vox Media talent could work with NBCUniversal properties.

While some big media companies make outright acquisitions, investments offer the chance to learn about the new digital landscape and benefit from a company's growth without taking on as much risk. The investments fuel the growth of the digital media companies and let them expand their relationships while remaining independent.

Stephen B. Burke, chief executive of NBCUniversal, said in a statement that the company was "excited to be making this investment and building a collaborative partnership involving editorial content, technology and advertising.".

The two deals represent the latest matchup between media giants and digital upstarts as the lines between the two worlds blur. Both sets of companies are rushing to understanding the other's business as people's media habits rapidly change.

Additionally, NBCUniversal, which is owned by Comcast, is preparing to make an investment of about $200 million in BuzzFeed, the digital media hub known for its trending quizzes, shareable lists and push into journalism, according to two other executives who also spoke on the condition of anonymity. That deal would value BuzzFeed at about $1.5 billion, they said. A BuzzFeed spokeswoman declined to comment.

Vox Media, a publishing house for the digital age, has landed a $200 million strategic investment from the entertainment group NBCUniversal, forming a partnership between the old and new media companies to collaborate on technology, advertising and programming.

"There is a respect that companies like ours do what we do well, and there is kind of a healthy respect for enabling our independence.".

Mr. Bankoff said that both Vox and NBCUniversal had much to learn from each other. He said his company had developed expertise in creating strong digital brands that resonate with millennial audiences, as well as new advertising formats. Vox can tap NBCUniversal's experience in building audiences and creating long-form and short-form videos, he said.

The lofty valuations of the digital media companies, which have exploded in the last year, are fast approaching the size of traditional media rivals like Time Inc., which has a market capitalization of $2.4 billion, and Meredith Corporation, at $2 billion.

Announced on Wednesday, the deal values Vox-- home to eight thematic digital media brands including the sports-focused SB Nation, the video game site Polygon, the tech site The Verge and the news hub Vox.com-- at about $1 billion, according to an executive with knowledge of the negotiations who spoke on the condition of anonymity.

Television companies are trying to ramp up their digital prowess, especially as their ratings deteriorate among younger viewers. At the same time, digital media companies are pushing into television to expand their brands and earnings potential.

"Platforms ranging from Facebook to Twitter to Google to Apple allow us to distribute and create new content, and it is a much bigger ecosystem now, leading to much bigger companies with much bigger opportunities," Jim Bankoff, chief executive of Vox Media, said in an interview.

"With that as the foundation," Mr. Bankoff said, "there are a lot of things to explore.".