SAN FRANCISCO — With an ultra-slim notebook computer and online movie rental service unveiled Tuesday, Apple is building on surging Macintosh sales and doubling its bet on delivering video to portable devices and televisions over the Internet.

Apple's foray into the online movie rental business was widely expected, but chief executive Steve Jobs surprised some by pulling off alliances with all six major movie studios, including its fierce rival Sony Pictures and Universal.

Apple's movie offerings will be under terms similar to those Hollywood has dictated with other online movie providers. Users can watch films instantly over a broadband Internet connection or download and keep them for 30 days. They just have to finish watching the movie within 24 hours after starting.

Films will be available through iTunes within 30 days after they're released on DVD. More than 1,000 will be ready by the end of February, at $2.99 for older movies and $3.99 for new releases, plus $1 for high-definition versions.

The service, which launched Tuesday in the United States and will roll out internationally later this year, will work on Macs, Windows-based machines, iPhones, iPods or Apple TV set-top boxes, which got a significant makeover.