Contacts are your main lifeline in this world. They're your shops and fixers. They've also got their own problems. You can help them with those problems. In return, they'll help you source more contracts and help you gain reputation in their region, among other rewards.
As you climb in the underworld, you'll grow stronger with your own unique build with an assortment of stats and associated skill trees. Install various cyberware that enhance your capabilities further, including additional HUD elements. Utilize a variety of weapons and attachments, as well as alternate types of ammo.