Our last seminar before intermin crit in November was about history of compositing. I've watched a very interesting video on this topic few months ago.
Although, the 3/4 of video are spent on explaining the old techniques, looking at ground breaking innovations and pioneers of VFX, I still found it very useful and informative. It's good to know history of a specific process and how it changed throughout the years.
Yellow screen is probably the most interesting part as I've never heard of it before. It's a really weird process and only one was made and used by Disney ( e.g. in Mary Poppins film).