|This article or subsection has an associated category.||1900s|
|Decades:||1870s - 1880s - 1890s - 1900s - 1910s - 1920s - 1930s|
(stardates from 1900.0 to 1909 or reference stardates -1/00 to -1/09)
|Centuries:||18th century - 19th century - 20th century|
The 1900s was, on Earth's calendar, the first decade of the 20th century. Although this was a time period before Human formulation of stardates, in some systems this era simply lasts from stardates 1900.0 to 1909. The reference stardate system has this decade fall from stardates -1/00 to -1/09.