Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Video Microscopy of Colloidal Suspensions and Colloidal Crystals   Colloidal suspensions are simple model systems for the study of phase
transitions. Video microscopy is capable of directly imaging the structure and
dynamics of colloidal suspensions in different phases. Recent results related
to crystallization, glasses, and 2D systems complement and extend previous
theoretical and experimental studies. Moreover, new techniques allow the
details of interactions between individual colloidal particles to be carefully
measured. Understanding these details will be crucial for designing novel
colloidal phases and new materials, and for manipulating colloidal suspensions
for industrial uses.

16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org
25
The categories of this paper are: patt-sol
36
The categories of this paper are: cmp-lg
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom