Graphs offer a generic abstraction for modeling entities, and the interactions and relationships between them. Most real world graphs, such as social and cooperation networks evolve over time, and exploring their evolution may reveal important information. In this paper, we present TempoGRAPHer, a system for visualizing and analyzing the evolution of a temporal attributed graph. TempoGRAPHer supports both temporal and attribute aggregation. It also allows graph exploration by identifying periods of significant growth, shrinkage, or stability. Temporal exploration is supported by two complementary strategies, namely skyline and interaction-based exploration. Skyline-based exploration provides insights on the overall trends in the evolution, while interaction-based exploration offers a closer look at specific parts of the graph evolution history where significant changes appeared. We showcase the usefulness of TempoGRAPHer in understanding graph evolution by presenting a detailed scenario that explores the evolution of a contact network between primary school students.