Well... I've read on some different sites about basic Indica and Sativa traits and then there are hybrids and lineages of different breeding from different continents and what was done in Cali and San Francisco in the 80's after the Reagan era forced growers underground and indoors.
You really have to read alot and it will all gel togteher after a while. Start with understanding the basic characteristics of high, taste, growth dynamics of sativa and Indica as well as the chemical makeupe ofthe high CBD% and THC% and how harvest affects sttrenght and characteristics of the high including harvesting early (cleaner energetic heady high) or late (stronger heavier body high).
Then you begin to understand the characteristcs of the Skunk#1 and the earl hybrids and why they were breeding for certain traits. After that different seed companies begin to go around the world and bring in different plants and work out the different penotypes to create what they are looking for in grow characteristics and high. This has been going on freely in the 60's and 70's but then there was a new era once indoor growing and breeding took place recently in history compared with other plants even though different cultures have been cultivating mary in their region for many many years. Read Michael Pollan's book the "Botany of Desire" and then get the cannabible by....
Those are good books to understand things. Others will have different info and books to contribute I would imagine. But start with understanding traits of Indica and Sativa which will speak more to the high and aspects of growth. Then you have to read and follow the lines of the "White" Strains in different places. Documentation and broader understanding might be had at Cannabis College in Amsterdam. It's constantly evolving and has very recently...
Fun stuff to understand and learn...