Cool software tools
Interesting tools for building diagrams:
These tools take as input a text file with a description of the diagram to produce and generate an image as output.
Graphviz [official web]
Simple but powerfull tool for graph visualization
PlantUML [official web]
Tool to build UML diagrams, wireframes, Gantt diagrams, mind maps, ...
Ditaa [official web]
Build general diagrams from ascii-art.
Mermaid [official web]
Visualize graphs, sequence, Gantt, class and git diagrams.
Interesting software to build presentations: