When your grandfather took his first job in construction, he probably knew a lot about ranch houses, dark paneling, and shag carpets. These days, even mentioning those things will get you laughed out of any respectable job interview. Trends change and being up on what’s current (and what’s not) will make you stand out amongst other candidates.
The trouble is, the trends you learned about five years ago probably aren’t the trends people are interested in today. Before your next interview, make sure you know what’s popular right now.