This interactive bar chart visualizes the UK prison population from 1900 to 2015, with buttons that let users explore different historical periods (e.g., 1900–1930, 1930–1960). Predefined selections highlight notable years, such as 1993, alongside explanatory text for each era. Built with D3 v5, it uses `d3.scaleBand`, `d3.scaleLinear`, and `d3.transition` for animated updates of bar positions and heights, driven by data from `uk_prison.csv`. Buttons load scenes defined in `data.json`, triggering zoom-like range changes and timed transitions.