Film critic and scholar Roger Ebert passed away at the age of 70 earlier today in Chicago, after a long fight with cancer. He had been battling cancer in both his thyroid and salivary glands for the past decade before his passing.

Roger Ebert became the Chicago Sun-Times film critic in 1967, just one year after joining the staff as a features writer. He also dabbled in screenwriting, taking a leave of absence at the Sun-Times to write Beyond the Valley of the Dolls for director Russ Meyer, a follow-up to 1967's Valley of the Dolls. He was given an ultimatum by editor James Hodge, to choose between filmmaking and criticism, and he chose the latter, largely due to his partnership with fellow critic Gene Siskel.

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In 1975, he launched the TV program "Coming Soon to a Theater Near You" with Chicago Tribune reviewer Gene Siskel, which ran in the local Chicago area, at first. The program was picked up for national distribution by PBS in 1978, and re-titled At the Movies in 1981. The program moved to Tribune Broadcasting in 1986, when the duo first started their "thumbs up, thumbs down" ratings system. Here's what Roger Ebert had to say in a past interview about coming up with that innovative system.

"When we left to go with Disney...We had to change some things because we were afraid of [violating] intellectual property rights. And I came up with the idea of giving thumbs up and thumbs down. And the reason that Siskel and I were able to trademark that is that the phrase 'two thumbs up' in connection with movies had never been used. And in fact, the phrase 'two thumbs up' was not in the vernacular. And now, of course, it's part of the language."

Roger Ebert left the TV program in 2006 due to his fight with cancer. Earlier this week, he announced on his blog that he was taking a "leave of presence" from his work, due to his deteriorating health.

He also authored 17 books throughout the years and hosted an annual film festival dubbed "Ebertfest," which featured overlooked films he thought deserved their just due. He is survived by his wife, Chaz Hammelsmith, a step-daughter, and two step-grandchildren.