As Paul (
@sour_grapes) said, EC-1118 is a workhorse. It will ferment a rock if given the opportunity. Fast reproducing, it has the killer factor so it stomps out competition, and high ABV tolerance so it can handle most musts. It's the most common yeast used in kits as it gives beginners with no experienced help the best opportunity to achieve success on the first try, and every try.
That said, EC-1118 brings little else to the table. Other strains impart their own character to the wine, so you'll see a fair amount of discussion on WMT regarding which strain to use for a given wine. In recent years I don't use EC-1118 as my primary yeast, but always keep a couple of packets in the fridge since if I have a fermentation problem, inoculating with EC-1118 will be high on the list of solutions.
I recently started a high ABV kit, using RC-212 as the primary yeast -- the description reads:
Ideal for full bodied red wines. Emphasizes fruit and spice notes, accentuates character in red grapes.
However, RC-212 has an ABV tolerance of about 16%, and this wine is in that range. The fermentation slowed down below 1.010 and I suspected it wasn't going to finish dry, so I added an EC-1118 starter to finish it up. This way I get the character I want from the RC-212 and the EC-1118 brought the ferment to completion. My notes on making an overnight yeast starter are
here.
There are numerous yeast strain charts floating around the net. Download a few and look at the descriptions -- yeast is among the cheapest ways to experiment when making wine, especially as you're looking to up your game.