What is big data for geospatial analysis?

Big data in GIS refers to very large, often fast-growing spatial datasets that challenge traditional storage and processing: sensors, GPS traces, satellite time series, point clouds, or billions of reports.

Techniques: cloud storage, distributed processing, tiling, streaming, and summarization for visualization. In web GIS, often only viewport-relevant parts load via bbox queries or vector tiles.

Big data is not synonymous with "many layers on a map." Volume, velocity, and variety require different architecture than a single shapefile or WFS layer.