More specific? In short, as the others have said, nodes and splines.
but here's what I wrote over a year ago on the release of X3.
Specifically, I'm talking about editing tempo maps, where the tempo ramps up and down, sometimes in very short amounts of time - something that applies to scoring, to orchestration, to commercial music cues - i.e. not some obscure feature. It's also a great effect in abstract electronic, pop, rock. Rather than just jumping to a new tempo there is a curve or slope. The instrumentation plays along with this slope.
The current state of the tempo draw tool is woefully unwieldy for doing this with any degree of precision. Not even any "smart tool" curves and lines, just a pen and a really hard-to-read, spreadsheet-like table.
Try this. Take a project that is MIDI data, open the "Tempo View" window, and draw a bunch of tempo changes. Have them slope 1 or 2 bars, or even 4 or 5. More or less simple. Now go in change those tempos to be a bit little faster and slower, by 1 or 2 or 3 or 10 BPM. Or change the length of the slope leading up to a new tempo change but landing on a precise beat. I'm not saying it can't be done; I've been working around this for 10 years. I just wish Cakewalk would truly bring all aspects of their program up to date, rather than just throwing more VSTs at us.