For anyone who has taken some level of investigation into the world of culture and religion, one may have already found that Jews and Judaism are unique, because in a way, it is not a religion. Some Jews are religious, others are not, still some are atheists, that's because generally speaking, Judaism as a religion is not faith based, but rather action and community based. For most religious Jews, your belief is not nearly as important as your observance of a set of codes known as "Mitzvot." There are Jews who study Buddhism, sometimes known as "Ju Bu's," even Satanism takes from Judaism's mystical branch of Kabbalah.
So simply put, Judaism is not just something one "believes in," which makes it technically not a religion as most others. What is Judaism then? There is no one answer to this, anyone who tells you otherwise, you have to remember, there are usually at least three opinions for two Jews, a common joke. There are things that Judaism and Jewlry is like. It's like a big fraternity, and like a gang, complete with initiation rites, historical indoctrination, and codes. It's also also like a big unconventional people force that legend says are tasked with bringing an era of physical prosperity and spiritual enlightenment on earth.
There are three ways to be a Jew, and that is by birth, by marriage, and by conversion. For those with knowledge of how the military works may relate it to commissioning in the military. Like the military, there are multiple ways to earn one's commission as an officer, with advantages and disadvantages. Indeed, your conversion rabbi is your "recruiter," belief isn't enough, the education and trial period is usually at least a year. And there is a custom to deny the conversion candidate three times before the process officially begins.
By birth: this is like direct commission or if someone is Jewish by blood, but went so far off from the culture and history of Jewishness that one has to go through an indoctrination process, like OTS. This is a good deal, you don't really have to do much and you know the ins and outs of everything. You know what's bullshit and what's not, just like prior enlisted officers who already knows his stuff through experience. You probably have a well rounded respect for customs and courtesies, kissing the mezuzah, davening, etc. You don't over do it, yet you know you don't need to. If you ever see an Israeli at an orthodox event, he or she is probably not dressed very formally, and probably doesn't care either. This of course is a generalization.
By marriage: this is pretty much like ROTC. Saying you became a Jew because you fell in love with a Jewish person is like saying you joined the army for college, but chances are no one gives a shit. Some of the best officers were ROTC, and some of the best Jews presumably converted for love. There is one advantage to converting this way, is you get the best of the two worlds, you are much in tune with the Gentile world, and at the same time you have your future spouse as your personal mentor much like an NCO instructor. Jewish marriages are fun, you get to party just like ROTC cadets before their 0500 PT session. Like an NCO, your spouse can show you the ropes and gives you the ins and outs so you're all squared away knowing the real ways of Jews, not just from rabbis and books.
By spiritual conversion: Some of the most famous Jews were converts, from Rahab to Herod, even King David's ancestry has at least a converted Jew. Spiritually converted Jews are like West Point or Marion Military Academy graduates. There is a joke that you can tell a convert by noticing the most normal person in the synagogue. That's because both West Pointers and spiritual converts have the potential to be the most brainwashed types. People sometimes look at you with suspicion when you tell them you converted because you found your spiritual calling or something, which is like an officer telling you he joined for "God and country." People may think you daven in your sleep and eat mannas for breakfast probably as West Pointers are stereotyped to salute tables and chairs, and anything that moves.
I say with a joking attitude about being brainwashed. Judaism leaves nothing unquestioned. Books and libraries called Talmud or Oral Torah, are written just to record the various debates that come up, some redundant, some funny, and some ridiculous. synagogue can be compared to a forum in a Greek city state. As the term "Yisrael" ישראל , which literally means to fight a or the deity, arguments are often taken as a good thing, as it keeps one in touch with the truth, whatever that may mean to the individual.
Whatever the conversion method, or ways to be Jewish. Once you're a Jew, you're a Jew, pretty much. Think of Gentiles as muggles, and Jews as wizards, and Yeshiva as Hogwarts, you're joining a community that separates itself from others. For most people, conversion is not recommended. If you want to go to Heaven, Christianity and Buddhism are good options. If you want inner peace and relaxation, Islam believe it or not is good. If there is one word I would like to use to describe Judaism, that would be counterintuitive, it's such a misunderstood, religion, community, and concept. Much like the opposing triangles that make up the Star of David, Judaism goes against many if not all preconceived notions. There are many ways to associate with the Jews without joining them as converts, such as through Noahides or even Freemasons. It's a fascinating topic that won't disappoint the would be Indiana Jones and truth seekers. Hopefully this shed some light on some otherwise not so well known perspectives on the esoteric community of Jews.