I notice that we have tags "20th-century" and "1900s"; these would mean the same thing for many (not necessarily most) of us. For others, the alternative numerics (1900s) refers not to a century, but a decade.
General notions of dates/era, etc. are important to our work, so taking a thoughtful approach to tagging would be a good thing for us to do.
From the Wikipedia entry about "Century," I note, "There is no "zeroth century" in between the 1st century BC and the 1st century AD."
From the same source, "Besides the Gregorian calendar, the Julian calendar, the Aztec calendar, and the Hindu calendar have cycles of years that are used to delineate whole time periods; the Hindu calendar, in particular, summarizes its years into groups of 60, while the Aztec calendar considers groups of 52."
The Wikipedia entry talks about "Alternative naming systems," and gives examples of such for, in particular, Sweden, Norway and Finland. Adding, "The same system is used informally in English. For example, the years 1900–1999 are sometimes referred to as the nineteen hundreds (1900s). This is similar to the English decade names (1980s, meaning the years 1980–1989)."
Perhaps others will add more about the possible confusion with "decades."