Progression
Before we delve into APB's "leveling system," you'll want to pull up your Character Info screen. By default, your J key is assigned to this task. Once you've got it up, you'll be able to read about all sorts of things, all of which contribute to the primary indicator of progression: your Rating.
Rating
At any time, you may check your overall Rating to see how far you've come. This number, which is located in the upper-left region of your Character Info screen, is the truest indicator of your current "level."
Whenever your Rating increases, a bevy of new opportunities will be provided for you. Beyond the availability of additional assignments, you'll be able to purchase more goods in San Paro's stores. While some of the items have other requirements, their Rating restriction is generally the easiest to meet, while the rest are the most complicated.
As for those other statistics which help this number grow, we'll start exploring them next.
Contacts and Organizations
Contacts (e.g., Double-B, LeBoyce) are among the first people you'll meet in APB, and you'll want to impress them. Whenever you're in the vicinity of a Contact, you'll usually be able to carry out missions in their names. As you may know, you can start completing assignments for the aforementioned characters within the Tutorial Mode. When you're granted access to the Financial and Waterfront Districts, don't forget where you came from -- find and impress even more Contacts!
Whenever you want to check on your Contact and Organization levels, pull up your Character Info screen, and click on the Progression tab.
As of this writing, your level with any particular Contact cannot exceed six (6). Nonetheless, you'll want to cap out your Contacts' levels as soon as possible; when you do, newer, higher quality weapons can be purchased within their stores. When your level with a Contact reaches three (3), one shiny toy is unlocked; once you cap them out at level six, they hook you up yet again! Though some NPCs don't adhere to this pattern, they're usually the cream of the crop; they'll provide you with more toys, not less.
Furthermore, after you've reached the maximum Contact levels, you can't impress the individuals further, but you can continue to build your reputation with their Organizations. To increase your overall "level" (detailed below), complete as many assignments as possible, and do your best to survive. If you can fight your way through the day with a minimal amount of defeats (or better yet, no deaths whatsoever), you'll be well on your way to impressing your Contacts, their Organizations, and you'll increase your Threat Level. Speaking of...
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