Fig. 1

Different levels of resolution are of interest, depending on the research question and the data available. Thus, analysis tools and reference systems (such as cell atlases) will have to accommodate multiple levels of resolution from whole organs and tissues over discrete cell types to continuously mappable intermediate cell states, which are indistinguishable even at the microscopic level. A graph abstraction that enables such multiple levels of focus is provided by PAGA [14], a structure that allows for discretely grouping cells, as well as inferring trajectories as paths through a graph