This line chart tracks the cumulative number of VizHub users from its launch in August 2018 through mid-2021, with each data point marking total user counts at sampled dates. The SVG visualization uses D3 v4 APIs including `d3.scaleTime`, `d3.scaleLinear`, `d3.axisBottom`, and `d3.axisLeft` to render axes, while `d3.line` draws the growth trajectory and circles highlight individual observations. Annotations from the `d3-svg-annotation` library label key events such as a Medium post and the VizHub 2.0 Kickstarter, with connector lines pointing to specific data points. The chart’s gridlines and tick styling come from CSS overrides, and user counts derive from the included `users.csv` dataset.