Numbers (for example, date and time, or any specific number or measurement: Length of a boat, number of witnesses, votes for a certain bill, score of a game, etc.)Statistics. Although technically just one form of number evidence, statistics are special enough to count as their own separate type of evidence, especially because they are so valuable at making evidence representative.Names (for example, place names, names of individuals, organizations, movements, etc.)Expert opinion (this refers to the use of someone else’s knowledge or opinion, not that of the author—when the author quotes or mentions a recognized expert in the field)Specialized knowledge (the author’s own knowledge, not common knowledge, usually acquired through some sort of formal training)