Single-clicking is sufficient :)
Also there are a lot of special clickable actions (mentioned in the FAQ > About section, or just keep clicking until you find something, there are 20+ special actions).
Also there are a lot of special clickable actions (mentioned in the FAQ > About section, or just keep clicking until you find something, there are 20+ special actions).
edit: Ha! Actually one can double-click on objects and get more info about their origin.