All this data is potentially out of date, and should be taken with a truckload of salt
What is hacking and what are hacking sites?
Hacking is a mini profession where you "hack" to open locked structures at Hacking sites to get the rewards they contain.
There are two types of hacking sites that you can get: Data Sites & Relic Sites. Both of them are Cosmic Signatures and you have to scan them down with your Probe Launcher first. For information on how to use them have a look at the Scanning Guide.
Where can I find hacking sites?
What do I need to hack?
Archaeology - gives you +10 Virus Coherence for each lvl of skill with Relic Analyzer
Hacking - gives +10 Virus Coherence for each lvl of skill with Data Analyzer
To use the Data/Relic Analyzer II the skills needs to be trained to level 5.
Data Analyzer I (+40 VC and +20 VS) or Data Analyzer II (+60 VC and +30 VS)
Relic Analyzer I (+40 VC and +20 VS) or Relic Analyzer II (+60 VC and +30 VS)
Cargo Scanner I/II - so, you'll never miss anything tasty anymore inside the containers
Afterburner I/II or Microwarpdrive I/II - the distance between some containers can be more than 50km, max range that i experienced was 280km
Expanded Cargohold I/II - to make sure your cargo bay can hold everything
Small Emission Scope Sharpener I (+10 VC with Relic Analyzer)
Small Emission Scope Sharpener II (+20 VC with Relic Analyzer)
Small Memetic Algorithm Bank I (+10 VC with Data Analyzer)
Small Memetic Algorithm Bank II (+20 VC with Data Analyzer)
Slot9 Poteque 'Prospector' Archaeology AC-905 (+5 VC for Relic Analyzer)
Slot9 Poteque 'Prospector' Hacking HC-905 (+5 VC for Data Analyzer)
I have found a site, how do I "hack" it?
External hacking guide
What sort of rewards should I expect from a hacking site?
The rewards for hacking sites usually fall under the following categories: