What are the examples of analog content provided in the passage? List them separated by semicolon.

Datafication is a technological trend turning many aspects of our life into data[1][2] which is subsequently transferred into information realised as a new form of value.[3] Kenneth Cukier and Viktor Mayer-Schönberger introduced the term datafication to the broader lexicon in 2013.[4] Up until this time, datafication had been associated with the analysis of representations of our lives captured through data, but not on the present scale. This change was primarily due to the impact of big data and the computational opportunities afforded to predictive analytics.

Datafication is not the same as digitization, which takes analog content—books, films, photographs—and converts it into digital information, a sequence of ones and zeros that computers can read. Datafication is a far broader activity: taking all aspects of life and turning them into data [...] Once we datafy things, we can transform their purpose and turn the information into new forms of value[2]

The examples provided in the above passage for analog content are: books; films; photographs.