Marvel movies are huge in today’s cinemas. We hear about this MCU, this Marvel Cinematic Universe. But what is it? The catch phrase of “It’s All Connected” is hard to believe, to be sure. How does this even work?

Hopefully, this article will explain all these questions and also bring you up to speed before "Captain America: Civil War" comes out this month!

It begins in May of 2008 with the release of "Iron Man."

The very first installment of the MCU, "Iron Man" kicked off the universe with an excellent start. In it, we are introduced to a minor character named Agent Coulson, who would eventually become the very glue that holds the MCU together, as well as a minor character in "War Machine" (James Rhodes aka Rhodey).

"Iron Man" ends with one of "Agents of SHIELD" Agent Fury’s coolest lines ever, “You think you're the only superhero in the world? Mr. Stark, you've become part of a bigger universe. You just don't know it yet. I’m here to talk to you about the Avengers Initiative.”

It was almost as if Fury was talking to the audience. But back then, the average moviegoer didn’t know what they were about to be sucked into.

After "Iron Man," the first bust of the MCU was released. "The Incredible Hulk" starring Edward Norton came out a few months after "Iron Man," still in 2008. Hulk movies have had statistically poor ratings for various reasons, and this one was only slightly better. I still believe it’s worth a watch, however, because, as we will explore, it has implications to the MCU as a whole.

It was also in "The Incredible Hulk" that we had the first crossover between movies, small though it was. In the post-credits scene we see Robert Downey Jr.’s Tony Stark approach "The Incredible Hulk’s" adversary General Thaddeus Ross.

They discuss the fact that Stark is forming a team, alluding to the Avengers many years before the actual events of the titular movie.

We find out in a Marvel One-Shot later, called “The Consultant,” that Stark was sent to sabotage allowing Emile Blonsky (Abomination) to be set free.

Two years after "The Incredible Hulk," the theater saw the return of the Iron Avenger in "Iron Man 2." A flop for most fans but a hit at the box office, "Iron Man 2" showed that it was the character and actor that sold the movies, not the plot.

However, it also saw the return of Agent Coulson, now given a first name, Phil.

Phil Coulson is present for the first half of the movie before heading to New Mexico, and it is also in "Iron Man 2" that we get our first real references to Captain America.

But most importantly, the character of the Black Widow, named Natasha Romanoff, makes her first appearance, played by Scarlet Johansson.

So far we have three of six Avengers introduced in the MCU over the course of three films. It is through Phil Coulson that we meet the next two. The second Marvel One-Shot now comes into play.

Remember when I said Phil Coulson was heading to New Mexico? Well, it turns out he was on his way to a crater in which Thor’s Hammer was found. The short One-Shot “A Funny Thing Happened on the Way to Thor's Hammer” features Phil Coulson on his way down south.

Next we come to the movie "Thor." "Thor" is where we meet the title character as well as his brother Loki, all amid the fantastical realm of Asgard. This was vital to the MCU because it introduced the first non-human Avenger and his adopted brother who would later become the main villain in Avengers.

Another important character introduced is Erik Selvig, an astrophysicist who is part of "Avengers, Thor: The Dark World" and "Avengers: Age of Ultron." It's also because of the Destroyer which is sent to earth by Loki to kill Thor that nukes begins being developed by SHIELD, which is an important plot point in "Avengers."

At the end of "Thor," we see Loki try to commit suicide by throwing himself from the broken Bifrost. Fan theories as to what happens to him vary, but somehow he ends up an ally of the Chitauri and Thanos. Also in Thor we have our first cameo appearance of Hawkeye, expert Marksman and future Avenger.

Our next movie jumps way back in time with "Captain America: The First Avenger." In the movie, set in the late 1940s, we see Captain America battle his way through Nazi Germany fighting HYDRA, the evil fictional Nazi science division.

HYDRA is very important, so remember that this is its first introduction to the MCU. Alongside Captain America, two other characters are introduced: best friend Bucky Barnes, and love interest/badass soldier Peggy Carter.

Peggy Carter would go on to found SHIELD with Tony Stark’s father, Howard Stark (who also happened to help make Steve into a Super Soldier). But in the meantime, Bucky falls off a bridge and is presumed dead while Steve crashes the enemy’s plane into the arctic and is also presumed dead.

But the most vital point in Captain America other than the introduction of the main character himself is the introduction of the Tesseract. Actually an Infinity Stone, the Tesseract is a power source and can create portals, called the Space Stone. This is very important for Avengers because SHIELD finds it in the ocean and begins experiments on it.

But remember how I mentioned Peggy Carter and Howard Stark? This is where the first of the MCU TV shows comes into play. "Agent Carter" features Peggy Carter struggling post-war as a woman in the intelligence agency.

Howard Stark makes a multitude of appearances alongside Edwin Jarvis, the inspiration for JARVIS, Tony Stark’s AI. The cast has many adventures and is overall a good show. Two seasons have run now, and a third is probably coming next January.

Flash back to the end of "Captain America: The First Avenger" and we see Captain America Steve Rogers awoken from stasis from an iceberg. Out of the ice and in the modern world, the end sees him trying to adjust to normal life.

This leads almost directly into the end of this first “phase” of movies in "Avengers." Now we have all six Avengers: Iron Man, Hulk, Black Widow, Thor, Hawkeye, and Captain America, as well as a villain, Loki.

Avengers is the culmination of what the heads at Marvel Studios call “Phase One.” To recap, Phase One includes "Iron Man," "The Incredible Hulk," "Iron Man 2,"Thor," "Captain America: The First Avenger," and now "Avengers."

The One-Shots that fit into this category are “The Consultant” and “A Funny Thing Happened on the Way to Thor’s Hammer.” Also, "Agent Carter" fits in here timeline-wise.

"Avengers," sometimes called "Avengers Assemble" overseas, is where we see all the Avengers in action together for the first time. It’s an incredible movie and made a ton of money in the box office, so I’m not going to spoil it for you too much in case you haven’t seen it (because you should go see it now -- seriously, now).

It ends with Loki in chains, Thor taking the Tesseract back to Asgard, Loki’s Scepter ending up in SHIELD’s hands, and the Avengers going their separate ways. All of this is important because of the upcoming films. But the most important thing of all is -- spoiler alert -- Agent Coulson’s death.

"Iron Man 3" kicks off “Phase Two” of the MCU. A total flop with fans but a big winner at box office, "Iron Man 3" saw not much new. It suffered from a poorly written villain.

But the important part of Iron Man 3 was that it highlighted the after-effects of Avengers, dealing with Tony Stark’s PTSD from the ordeal. Also, it featured the Hulk Bruce Banner in the beginning and end which was cool for fans.

After "Iron Man 3" we get the Marvel TV show known as "Agents of SHIELD." It started out slow but has since rebounded since about halfway through season 1. In it we find Coulson brought back to life (why is explored through the entire first and second seasons with a satisfying result) and forming a team of SHIELD agents.

Skye and Ward are the most vital characters to future plots. The majority of the first half of the first season runs alongside the MCU through the next movie, "Thor: The Dark World."

"Thor: The Dark World" sees Thor and Loki forced to work together to stop Malekith the Accursed from changing the universe back into a universe of darkness using the Aether. The thing to know about this movie is that Loki is presumed dead at the end but is revealed to have taken the All-Father’s place in disguise as King of Asgard.

The other vital plot point is that the Aether is actually the Reality Stone, another of the Infinity Stones like the Tesseract. It hasn’t be revealed just what the Aether can truly do, at least not yet. At the end with Malekith defeated, the Aether is delivered to The Collector, an alien who will come into play in a later movie, "Guardians of the Galaxy."

Perhaps the most influential film in Phase Two, "Captain America: Winter Soldier" sees Steve Rogers working for SHIELD after Avengers. But something’s wrong. He gets attacked by a man with a metal arm and it’s then revealed the HYDRA has taken over the highest ranks of SHIELD all the way through the bottom.

Cap works with Black Widow, Fury, and Maria Hill, along with a new friend, Falcon (Sam Wilson) to stop HYDRA and this metal armed assassin. Well, it turns out this “Winter Soldier” is actually Steve’s long lost best friend, Bucky Barnes. Bucky was experimented on and brainwashed into being this soldier.

At the end, SHIELD is dismantled and Bucky, running away, begins remembering his old life. In the post credits scene, we also see our first glimpse of two new characters to come in "Avengers: Age of Ultron": Quicksilver and Scarlet Witch.

This throws a wrench in "Agents of SHIELD," and suddenly the show takes off and never slows down again. Agent Ward is revealed as HYDRA and he becomes super evil as the seasons progress.

The next movie is completely different. "Guardians of the Galaxy" takes place way out in the galaxy and deals with a new Infinity Stone, the Power Stone. I will not go into detail about what happens because this is arguably the best Marvel movie ever and you should watch it. Just know that the Power Stone is now accounted for.

Then we move into season 2 of "Agents of SHIELD." It’s awesome. Go watch it. Skye is revealed to be the comic hero Daisy Johnson, an Inhuman.

The next movie was "Avengers: Age of Ultron." A good movie, it introduces several new themes. First, we find out that the gem in Loki’s Scepter from the first Avengers movie actually contains an Infinity Stone: the Mind Stone.

With it, a new character in Vision is created. But it also gave the twins, Quicksilver and Scarlet Witch their powers, meaning at least Scarlet Witch is super powerful.

Ultron, the villain, is defeated but part of a country is destroyed. Talk about billions of dollars of damage. Quicksilver gets killed protecting a child and Hawkeye, and the Avengers disband. Hawkeye goes home to his wife and kids, Thor goes to Asgard, and Tony Stark just leaves.

The New Avengers are formed: War Machine (Iron Man franchise), Vision, Scarlet Witch, and Falcon (Cap 2) under the guidance of Black Widow and Captain America.

The final movie before this upcoming Captain America was Ant-Man. A total hit, Ant-Man deals with introducing a new hero and is definitely an origin story. It’s hilarious. It’s in my top five Marvel movies.

There are two shows I didn’t touch on: "Daredevil" and "Jessica Jones." Both are excellent shows, definitely on the darker side of television. They are on Netflix and are kind of like origin stories as well. They don’t cross over as much with the movies simply because they are on Netflix so they come out all at once. But check them out!

To recap before "Civil War":

Avengers lineup is Black Widow, Captain America, War Machine, Vision, Scarlet Witch, and Falcon.

Winter Soldier is unaccounted for.

Infinity Stones found: Mind Stone, Power Stone, Reality Stone, and Space Stone.

Shield is gone (secretly being reformed in the TV show).

Trillions of the dollars in damage has come from Avengers movie events.

There you go! Hope you enjoyed this, and will enjoy "Captain America: Civil War."