[nctomatoman]

Here is how I look at the three main tomato classes:

Indeterminate - infinite upward/outward growth, reaching 8 feet or more by the killing frost, suckers become nearly as long as the central leader; potato or regular leaf foliage, non-crinkled (rugose), high foliage to fruit ratio. Most tomato varieties are indeterminate - examples are Better Boy or Cherokee Purple

Determinate - look identical to indeterminate varieties as seedlings and during initial growth, but flowers set at branch ends once vertical growth stops (so-called self topping characteristic first seen with Cooper's Special in the early 1920s), tend to have a concentrated fruit set - potato or regular leaf foliage, non-crinkled (rugose), high fruit to foliage ratio. Examples are Sophie's Choice, Taxi, Southern Night, Roma

Dwarf - Look distinct as seedlings, being more squat, thicker central stem, act as very slowly vertically growing indeterminate varieties, topping out at 3-5 feet, depending upon the exact nature (determinate or indeterminate - not easy to distinguish in some cases, and not all that important to know, really) - can be potato or regular leaf, but the foliage is a very dark green, nearly bluish green, and puckered/wrinkled (rugose), high foliage to fruit ratio. Been known since the mid 1800s, best known older ones are Dwarf Champion, Golden Dwarf Champion, New Big Dwarf; more recent one is Lime Green Salad, and the new creations from the Dwarf Project, such as Rosella Purple and Summertime Green.

Micro Dwarf varieties are very short growing Dwarfs, tend to be one foot or less in eventual height, and have the thick central stem and rugose foliage of Dwarfs.