Studies biology from a more global point of view, if putting all little pieces of an organism make up the final biological function.
Very good metabolism database.
Some things that they have of interest which may not be on NCBI:
Hits a free login wall after a few IP hits. And just a very normal casually browsing number of hits. What is this bullshit?
Database of promoter.
Here's a good example of what you can get out of it: E. Coli K-12 MG1655
For an example with context, have a look at E. Coli K-12 MG1655 and the second protein of the genome, e. Coli K-12 MG1655 gene thrA.
Each of the omics studies a subset of molecular biology with a data intensive and broad point of view that tries to understand global function or organisms, trying to understand what every biologically relevant molecule does as part of the hole metabolism.
The main omics are:
Omics might be stamp collecting, but maybe it is a bit more like Trading card game/Magic: The Gathering collecting, in which the cards that you are collecting actually have specific uses and interactions, especially considering that most metabolic pathways are analogous across many species.
Figure 1.
Hierarchical diagram of the major omics
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Integrating multiple omics, comes quite close to whole cell simulation.

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