First: What IS an economic cycle and why do we care? Basically, there are months and occasionally years at a time where companies have a really hard time finding people to hire and workers can ask for raises without fear of the consequences and service at fast food restaurants gets beyond terrible and traffic is a nightmare. At any given time, there is probably some place you can point to like this (North Dakota had its moment while the rest of the country groaned from lack of jobs, and commutes were, comparatively, a breeze and everyone at Wendy's was friendly, prompt and could make accurate change). There are, by contrast, months and occasionally years at a time where companies are spoiled for choice -- brilliant, experienced candidates willing to work long hours for cheese sandwiches and the hope of access to terrible health insurance they mostly have to pay for themselves, when asking for a raise is inviting your boss to fire you and the service at McDonald's is beyond amazing. And there are the bits in between. So that's it: the booms are when you wait in line to be treated awful at Carl's Jr., but you're making bank -- altho you still can't afford to buy a house because they went right to the stratosphere before you had your chance. The busts are when you are praying to get hired by Subway, because your however many months of unemployment has run out and it isn't going to get extended.
Second: What is the Fed? The Fed is the banks' bank. It's where banks get money. It's where banks deposit money. And the Fed gets to decide the interest rate charged when banks need money, and what they get paid on their money on deposit. If the Fed thinks that the world has gone apeshit, and all those incompetent idiots working fast food are buying McMansions because the banks are giving money in job lots to all comers, the Fed can charge the banks more money to discourage them from doing this. If the Fed looks around and say, traffic is entirely too light, and I think I was just served by a Nobel Laureate at Papa John's, then the Fed can charge the banks _less_ money to encourage the banks to more freely loan money to enterprising people who know what Ruby on Rails is, and have already used AWS at more than one gig.
Under W., the banks went apeshit, and everybody bought a McMansion, but for a variety of reasons, some good, but mostly bad, the Fed was unable the effectively intervene to put a stop to the lending, in part because a lot of the lending to buy the McMansions was not going through the banks; it was going through another part of the economy. Anyway, the crash happened, and then nobody wanted to do anything except hoard their folding green stuff, dollars, gold, etc., and the Fed reduced rates to effectively zero -- they couldn't GIVE money away, literally -- in the hopes that someone, somewhere, would borrow some money, start a business, hire some people, etc., especially that amazingly brilliant logistics person who was pushing a broom at Sorrento's.
Third: What is the September Meeting? Well, along about the middle of September, the people in charge of the various member banks of the Federal Reserve (you know where Wikipedia is. Go read all about it) will get together and have a convo and then they will put out a press release and Janet Yellen will talk to the press. While Yellen has been ridiculously clear that rates can be changed at any meeting, with or without a pre-schedule press avail, there is this idea that a rate change -- the first in YEARS!!! -- will occur at a meeting with a pre-schedule press conference. And a lot of people are utterly convinced that Yellen will announce a rate rise.
Fourth: The rate rise, whenever it occurs, will be tiny. So tiny that it will have effectively no effect, unless a lot of people who aren't talking decide to throw another Taper Tantrum.
Read about that on your own, say, here: http://www.investopedia.com/articles/personal-finance/060415/what-taper-tantrum-and-should-you-fear-it.asp
Fifth: Wait, what?
Remember that the basic idea behind raising rates is because the economy is On Fire and the service at Burger King has deteriorated unacceptably, plus it takes so fucking long to get to work that road rage incidents are on the rise and businesses are having trouble expanding because when they hire the most competent person they can find (until recently, employed as an assistant manager at Little Caesar's), that person turns out to be unable to get along with anyone, erratic about showing up to work on time and prone to lunches involving a lot of alcohol. Is that how the world is working right now?
Crickets. I hear crickets. Loud, loud crickets.
Now, in favor of the rate rise argument are the lovely people of Mountain View, California, who put a cap on new office space. Also, an organization called Save Our Suburbs in Mercer Island which was formed in response to the possibility that the population of Mercer Island might start to rise as a result of Transit Oriented Development around their Link station. It is clear that the economy of Mountain View, and the quiet, heavily patrolled burbs of Mercer Island (don't drive in Mercer Island while black, or, hell, even if you're in a beater car. They'll escort you off if you even look slightly lost and are white) are enjoying an excellent point on the economic cycle.
Against the rate rise argument are BLS statistics indicating absolutely no wage growth whatsoever. Not only are we not at the happy cusp that is NAIRU (look it up -- best reason ever to raise rates, I do in fact worship at the altar of Volcker, while wistfully looking back in nostalgia at how _fast_ runaway inflation ate away at mortgage debt in the 70s that had been priced in the late 1960s), with energy prices plummeting and every other commodity chasing energy downhill, it's not clear we have any kind of inflation at all.
Then why do people expect/want the Fed to raise rates?
I'll tell you why. Our country has a lot of older people in it (you know, like me, only slightly more so). And they are TERRIFIED of investing their money in anything that isn't guaranteed by the US taxpayer six ways or more. And that means that the Fed rate totally determines how much they can take out each year of their retirement (or, if slightly younger, how long they have to wait before they can retire) and they aren't happy about it.
Basically, the olds want the Fed rate to go up, so they can retire. And if that happens on the backs of the middles and the youngs, well, they'll just pretend they don't know that's gonna happen and act all shocked if they get their way and then it does.
Good news! I think the Fed is a lot more clever than they are. But we shall see.
ETA: I have actually left out of this overview an important argument in favor of raising rates. It is important NOT because it is a good argument (it is breathtakingly immoral and also risible) but because the people who emit this argument look like reasonable people and often have business degrees or otherwise look like they might actually know something. Here it is: we should raise rates NOW so that if there's another downturn, we can lower them again.
Of course, given that the single most predictable result of a rate rise or series of rate rises IS another downturn, well, yeah. Immoral. Risible. Now, you might be thinking, wait, they might have a point. To which I will politely refrain from saying, Try, Try Really Hard, To Not Be a Mark, and instead say this. Well, if we have another downturn while rates are effectively at zero, we will just have to resort to ACTUAL stimulus, rather than somehow acting like the central bank is the only person who can possibly do something about a downturn. You know, ACTUALLY FUND INFRASTRUCTURE type of thing. New Deal. Etc. Ideally while avoiding the really bad scenario for jump starting the economy (you remember that one: destroy all the existing everything by having a really comprehensive war. Afterwards, the group with the biggest surviving industrial base makes a ton off of loaning the rest of the world money to buy everything they need to rebuild. Also known as the 1950s).