Marx's analysis of a capitalist system begins by postulating that it's fundamentally composed of units called commodities.

In the capitalist system commodities have two features.

1. They are produced

2. They are produced by capitalists

Capitalists produce commodities by employing workers to produce them.

In this section, Marx begins his analysis of the first feature of the capitalist system (viz. that it is commodity producing). Workers and capitalists will not appear in Marx's analysis for several more chapters.