Self-tutoring about regular expressions with JavaScript: the tutor mentions the idea of the boundary condition. In JavaScript regex, a boundary condition can mean a whitespace or punctuation before or after a word. That’s my understanding, anyway. Source:

Self-tutoring about Linux: the tutor mentions awk. awk is a utility for getting values from tabulated data. It works line by line. For instance, awk ‘{print $2}’ input.txt will print the second field in each record of input.txt. Source: