Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: QCD and Weak Interactions of Light Quarks   This review contains an overview of strong interaction effects in weak decays
starting with a historical introduction. It contains a short overview of
semileptonic decays and their relevance for measuring CKM matrix elements. The
main part is devoted to the theoretical calculation on nonleptonic matrix
elements relevant for $K^0$-$\bar{K^0}$ mixing and $K\to\pi\pi$ decays. It
concludes with a short summary of rare kaon decays.

16
The categories of this paper are: stat
6
The categories of this paper are: astro-ph
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
23
The categories of this paper are: solv-int
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
4
The categories of this paper are: cond-mat
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
27
The categories of this paper are: comp-gas
8
The categories of this paper are: hep-ex