Caffeine is NOT addictive, but it sure is habit-forming. You don’t hear about coffee addicts robbing stores and hijacking motorists to get money for a fix. That’s because while caffeine does cause dependence, it isn’t in the same category as opiates or alcohol.
Dr. Peter Martin, Director of the Institute for Coffee Studies at Vanderbilt University Medical School says coffee’s not highly addictive and describes caffeine as having “minor-league side effects compared to real addictive drugs.” 
People casually describe themselves or others being addicted to caffeine. But for some (not all) users, it’s more of a physical dependence than an actual addiction.
The Merriam – Webster dictionary defines addiction as the:
compulsive need for and use of a habit-forming substance (such as heroin, nicotine or alcohol) characterized by tolerance and by well-defined physiological symptoms upon withdrawal; broadly : persistent compulsive use of a substance known by the user to be harmful.
When a drug addict or alcoholic doesn’t get his poison, he may experience anxiety, jumpiness, shaking, trembling and fatigue. The addict who is unable to get a fix can sweat, vomit, lose sleep, lose appetite and have headaches and irritability.
The National Council on Drug Alcoholism and Drug Dependence has a long list of the signs of addiction, including the following: 
Blacking out or experiencing memory loss
Arguing or fighting with family members or friends
Experiencing irritability, depression, or mood swings
Using substances to feel “normal” or to change the mood and relax or cheer up
Difficulty sleeping or dealing with problems without using
Experiencing headache, panic attacks, insomnia, nausea, diarrhea, sweating, tremors and shaking, nightmares, hallucinations, or other unpleasant withdrawal symptoms
Changing appearance, including flushed skin, discolored eyes, and broken capillaries
Using alone, first thing in the morning, or in inappropriate or risky situations
Keeping substance use secret or lying about how much or frequently you use
However, the Health Care Resource Centers (HCRC) described addiction as more than compulsiveness: 
Individuals can be addicted to not only substances, but people, activities and things that bring them a feeling of joy or satisfaction. Unfortunately those feelings are often short-lived and more and more of their “drug of choice” is needed to bring about the satisfaction they are seeking. This is the chronic, relapsing nature of the disease of addiction. It is neither a moral failing nor a lack of willpower.
Being “addicted” to caffeine shares some traits with outright addicts, although not to the level of compulsive need described above.
Caffeine junkies also build a tolerance for where they need more of it to get the same stimulating effects as they had the first few times they used it.
They also may build a dependence on it to where they feel some withdrawal symptoms if they don’t get their usual dose.
Caffeine withdrawal symptoms for some but not all regular users include headaches, irritability, depressed mood, difficulty concentrating and sleepiness.
And Live Science states that regular caffeine users who wake up groggy, depressed and tired are actually experiencing withdrawal symptoms. 
Caffeine Use Disorder
The Journal of Caffeine Research said in a 2013 article that there’s such a thing as caffeine use disorder: 
Caffeine is the most commonly used drug in the world. Although consumption of low to moderate doses of caffeine is generally safe, an increasing number of clinical studies are showing that some caffeine users become dependent on the drug and are unable to reduce consumption despite knowledge of recurrent health problems associated with continued use.
And the World Health Organization plus some health care professionals recognize caffeine dependence as a clinical disorder.
A journal on DSM-5 Caffeine Use Disorder Research Diagnosissays this is marked by: 
(1) persistent desire or unsuccessful efforts to cut down or control caffeine use, (2) continued caffeine use despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by caffeine, and (3) characteristic caffeine withdrawal syndrome or caffeine use to relieve or avoid withdrawal symptoms.
Caffeine isn't addictive
But WebMD says caffeine being addictive is nothing but a myth: The article says: 
This one has some truth to it, depending on what you mean by “addictive.” Caffeine is a stimulant to the central nervous system, and regular use of caffeine does cause mild physical dependence. But caffeine doesn’t threaten your physical, social, or economic health the way addictive drugs do. (Although after seeing your monthly spending at the coffee shop, you might disagree!)
Unlike true addicts, caffeine users don’t lose control of their habit, shun the society of friends and family, take risks and commit crimes to get their caffeine, and they don’t change their appearance, neglect hygiene and have big personality changes.
They do share some traits with outright addicts, including building a tolerance for caffeine where they need more of it to get the same stimulating effects as they had the first few times they used it. They also may build a dependence to it to where they feel some withdrawal symptoms if they don’t get their usual dose.
How to stay on top of your caffeine intake
Did you know that there’s such a thing as caffeine cycling?
It’s how some caffeine junkies stop taking caffeine temporarily so they can get the euphoria and thrill of the stimulant that they got at first.
Caffeine cycling for chronic users brings back that old black magic. If you’re a regular or chronic caffeine user, you may have noticed the stimulating effects of the substance aren’t as strong as when you first started to take caffeine. If you want to experience that near-bliss you used to get from that first cup of java, you can do caffeine cycling where you stop taking it for a while and then start again.
But if getting rid of caffeine all at once sounds like a massive mountain to climb, then you can try taking it in smaller and smaller daily doses for a couple of weeks. You will find that you won’t get headaches or be extremely sleepy if you wean yourself from caffeine.
One tip that we like most? Try a pop or two of caffeine mints instead. You’ll get the same kick and that regular caffeine fix for a little less caffeine dose. It’s way easier to watch for your caffeine intake if taken mint after mint! (Viter Energy has 40 mg of caffeine a pop.)
Either way, rest in the fact that you’re NOT really an addict. Just someone who loves their regular caffeine fix!
If you want to know what caffeine does to our brain, watch this video:
Erectile dysfunction. In combination, those are two of the ugliest words known to man. But can caffeine help you get it up?
Science hasn't found the definitive answer to this question, but one study concluded that fewer men who consume caffeine have problems performing. The study said:
Caffeine intake reduced the odds of prevalent ED, especially an intake equivalent to approximately 2-3 daily cups of coffee (170-375 mg/day). This reduction was also observed among overweight/obese and hypertensive, but not among diabetic men. Yet, these associations are warranted to be investigated in prospective studies