A cam lock is a rotating type lock found on a variety of window types. When turned closed, cam locks are designed to pull the two sashes tight together for improved security and energy efficiency. Lift Lock is a modern alternative to the traditional cam locking system for double hung and single hung windows.
A keeper is the stationary half of a cam lock.
Up until the middle of the 19th century, large panes of glass were fragile and expensive to create, so muntin bars were joined together in order to create large expanses of glass from smaller individual panes. When historical accuracy is important, windows can still be made with muntin bars or sometime referred to as authentic divided lite
(ADL) (Not shown).
Simulated Divided Lite Bars
Because large panes of glass are now stronger, less expensive to manufacture, and more energy efficient, muntin bars have largely been replaced with Simulated Divided Lite bars (SDL), which rest on the surface of the glass.