A bar is a small production line with a handful of roles, and the roles are not interchangeable. Learn them before your first shift, because most of what a new bartender gets wrong is not the drink — it is not knowing whose job something is and either doing it badly or leaving it undone.
Barback
The barback keeps the bar supplied so the bartender never has to leave it. Ice, glassware, beer, kegs, liquor from the back, garnish, trash, spills, restock between waves. On a busy night the barback is the reason the bar functions, and a bartender working without one is doing two jobs at once and will be slower for it.
This is also the most common way into the trade. It pays less than bartending, it is the most physical role in the building, and it puts you inside the bar where you can watch specs, speed and the point of sale for months before anyone asks you to perform. Module 5 treats it as the main route in, because it is.
Bartender on the stick
The bartender working the guest-facing bar: taking orders, making drinks, running tabs, watching the room. "On the stick" means you are on the rail serving people directly, as opposed to working service tickets. In a large bar there may be several stations, and which station you are given on a given night can matter more than the bar's overall volume — the well at the service end and the station by the door are different jobs with different money.
Service bartender
The service bartender makes drinks for the dining room's servers off printed tickets and has little or no guest contact. It is a pure execution role: high volume, fast, precise, no personality required. Because there are no guests there are no direct tips, so income arrives through the servers' tip-out. That structural detail matters enough that Module 1 treats service bar as its own segment.
It is also a good place to be new. Nobody is watching you while you learn to build six drinks at once.
Bar manager or beverage director
Ordering, inventory, cost control, menu and specs, scheduling, and — the part that concerns you — hiring. In most independent venues the bar manager or general manager decides who gets hired and who gets the good shifts. In larger operations there is an HR layer that filters applications, but the person who actually wants you is still the one running the bar.
The lead or head bartender is usually not a manager in title but is often the person whose opinion decides your trail. Treat their read of you as the interview it is.
Servers, runners, hosts
If the venue has a dining room, servers are simultaneously your colleagues and your customers. They ring drink orders that you make, and in most structures they tip out a share of their sales or tips to the bar. That means your income is partly a function of how well the floor sells and how well you keep their tickets moving. Food runners and hosts are often in the same tip-out web. Module 1 explains who pays whom and how the percentage is calculated, because it is the number people most often fail to ask about.
Kitchen, dish, security
The kitchen decides whether your guests get fed on time, which decides whether they stay for the second round. The dish pit decides whether you have glassware, which on a busy night decides whether you can serve anyone at all. The door or security team decides who comes in and is the person you call when a situation at the bar stops being yours to manage — knowing when to hand something over is a skill, and Module 4 covers it.
There is a practical version of all this: be liked by the dish pit and the barbacks. They control the two things that stop your night dead, and they are the two roles most often treated as invisible. That is not sentiment, it is operations.
What this means for your first week
You will be told to do things by several people at once. The general rule is that the bar manager sets policy, the lead bartender sets how it is done on the night, and everyone else is asking rather than instructing. When two of them conflict, do the thing that keeps the guests served, and ask afterwards — not in the middle of a wave.