"A trade secret is a formula, practice, process, design, instrument, pattern, or compilation of information which is not generally known or reasonably ascertainable, by which a business can obtain an...
An individual investor (non-institutional investor) can trade before or after market hours through ECNs (Electronic Communications Network). Your broker will have a ECN selection in a drop-down menu...
It's because the salon is typically opened Tuesday-Saturday, Saturday being the busiest day. It gives full time cutters the equivalency to a full weekend (2 days).