Craig Federighi, Apple's senior vice president of software engineering, said Monday that the changes will highlight the websites that people are visiting, and not the browser itself.
"We've in Yosemite been able to pack all of the power of the Yosemite UI into this single bar," he said. "There's more space for your content."
Apple has deleted most of the browser "chrome," the interface itself, for an extreme minimalist look that closely resembles Safari on iOS 7, Apple's iPhone and iPad operating system. The Favorites bar is hidden by default, although you can make it reappear through the Preferences menu.
Private Mode, the privacy-centered browsing option that allows you to browse the Web without adding tracking cookies or sites to your browser history, follows the lead of other major browsers that change the look of the browser interface to make it more visually distinct from a regular Safari window.
The new tab view shows you a snapshot of all your tabs at once, and allows you to create tab stacks from the same site.
The integrated Spotlight search lets you preview articles and search results without having to click through to the new page, similar to Google's search precaching in Chrome.
The browser finally adds WebGL support, a major win for developers looking to standardize 3D graphics and animations across browsers with HTML5. WebGL received early attention and support from Chrome and Firefox, and even Microsoft reversed course on it and added support with last year's Internet Explorer 11.
Federighi said that the browser will support "HTML5 Premium Video," which is a fancy way of saying browser-based digital rights management. That likely means Encrypted Media Extensions, the DRM modules favored by major Hollywood studios. However, Safari has a different DRM plug-in than Chrome and Internet Explorer, so it wouldn't be surprising to see developers forced to support each one if they want to run DRM video.
Federighi made a big deal out of the new Safari's ability to better manage battery life when running multiple tabs and media, and said that 1,080p video on Netflix, for example, will give your Macbook battery up to two more hours of life thanks to the DRM video upgrade.