Scientist: Log is the basis of the pH and Richter scales
Mathematician: Log is the integral of $\frac{1}{x}$
Programmer: A log is generated by a program to help in debugging
Lumberjack: Logs are what keep my buisness running
IT professor: There are two types of log: log in and log out
Camper: Logs are used to make campfires
There are clearly two types of log: a plaintext log, call a plog; and a binary log, called a blog