The Types of Origami Models According to the Number of Pieces of Paper Used

1. Single-Paper
In the old times, this is usually considered as the “true” origami models, years before the “one-paper” policy has been abolished. I wonder what bastard would implement such “one paper” policy crap or something.
Example: Crane (Traditional)

2. Multipiece Origami
This origami is made of two or more pieces of paper, folded into simple forms called “units.” The challenge usually is in the assembly, but if the model is made of a freaking large number of units (like a hundred), the challenge can also be in that too. It’s a cheaper and painless alternative to cremating your hands…:P
In the old times, multipiece origami is not considered origami. But now, the crappy “one-piece” (pweh!) is abolished (yey!).
Example: Mercury Kusudama (Makoto Yamaguchi)

2.a. Modular Origami
Modular Origami is a subset of Multipiece Origami, since……duh! We use lots of paper on this one too. But what makes it different? The units of Modular Origami have to be completely IDENTICAL. The Mercury Kusudama above uses 2 types of units: a cross-shaped module and a flowery thingy which is meant to be inserted in the middle. The TSU, shown below, has all its modules shaped like little dissected worms. o.O
Example: That Simple Unit (Charles Esseltine)