For my first two years of running, I just ran. Set myself a rough distance based on some online plan I'd downloaded (for a road race) and just sensibly increased my distance each run / week whilst trundling along at around 6-6:30 m/ks. As I started to get more into Strava I saw people posting runs with weird names like 800s with WDs and CDs and had no idea what they were talking about.
As part of my sign up to the Tarawera 50k (my first 50) I got two weeks of training with Squadrun added in. They're an online distance based coaching program at awesome value (NZ$10 a week type awesome!) headed by successful ultra-runner Kerry Suter and his partner Ali Pottering, also an avid trail runner. So pretty much these guys know what they're talking about hey.
The program consists of 7 prioritised runs a week of which you do what you're capable / able / wanting to do. It requires a fair amount of self-discipline and planning to get your allocated runs in around life and (eek dare I say) non-running activities. The runs range from long trail runs to short speed work and strength work (I smell hills!) with regular 5k and 10k time trials to check in with your progress and update your training paces.
Since joining them I've found new discipline in my running and most importantly my running has notably improved. My 10k time is sub 50min for the first time ever and I'm running regularly at about one minute faster per k.
Kerry & Ali are super supportive on email and Facebook. But most importantly they have created an amazing running family mostly active in NZ and Australia who cheer each other on during races.
Check them out - http://squadrun.co.nz/