The airlines and aircraft pages on my Flight Log behave in similar ways.
Airlines
The airlines page shows a list of airlines I’ve flown and the number of flights on each, sorted by number of flights.

Note: I later discovered that the flights shown here as Continental were actually on American Airlines. This has been corrected in the Flight Log.
When codeshares are involved, I use the airline and flight number of the operator of the flight.
Regional subsidiary airlines are listed as the parent airline. For example, all American Eagle flights are listed as American Airlines, and all flights branded as United Express are listed as United flights, regardless of which subsidiary airline actually operates it.
Airlines which have gone through a merger since my last flight are still listed as the airline they were on the date I took the flight. Thus, my flights on Northwest are not now considered Delta flights.
Clicking on any airline brings up a Great Circle Mapper map and list of all flights I’ve taken on that airline:

Flight map generated using the Great Circle Mapper—copyright © Karl L. Swartz
Aircraft Families
The aircraft families page shows a listing of all aircraft families I’ve flown.

A large portion of my flights are on regional jets; a hazard, I suppose, of living near Dayton, Ohio.
Note that I do not know the aircraft for every flight I’ve taken (particularly older flights), so those flights are not included in this listing.
As expected, clicking on an aircraft family brings up a map and list of the flights using it:

Flight map generated using the Great Circle Mapper—copyright © Karl L. Swartz
The next post will discuss the final two sections—classes and tail numbers.