Over the years I've received scores of e-mail queries from people seeking answers to basic questions about Buddhism. Here are my answers to some of the most common ones. These answers reflect my own opinions and interpretations and in no way represent a "definitive" Theravada Buddhist point of view. My hope is that these answers, along with the accompanying links and references to suttas and other texts, will serve as useful hints to steer you towards finding answers of your own.
The Buddha referred to his teachings simply as Dhamma-vinaya — "the doctrine and discipline" — but for centuries people have tried to categorize the teachings in various ways, trying to fit them into the prevailing molds of cultural, philosophical, and religious thought. Buddhism is an ethical system — a way of life — that leads to a very specific goal and that possesses some aspects of both religion and philosophy:
"Therefore, Ananda, be islands unto yourselves, refuges unto yourselves, seeking no external refuge; with the Dhamma as your island, the Dhamma as your refuge, seeking no other refuge."
— DN 16
Despite its non-theistic nature, however, Buddhist practice does call for a certain kind of faith. It is not blind faith, an uncritical acceptance of the Buddha's word as transmitted through scripture. Instead it is saddha, a confidence born of taking refuge in the Triple Gem; it is a willingness to trust that the Dhamma, when practiced diligently, will lead to the rewards promised by the Buddha. Saddha is a provisional acceptance of the teachings, that is ever subject to critical evaluation during the course of one's practice, and which must be balanced by one's growing powers of discernment. For many Buddhists, this faith is expressed and reinforced through traditional devotional practices, such as bowing before a Buddha statue and reciting passages from the early Pali texts. Despite a superficial resemblance to the rites of many theistic religions, however, these activities are neither prayers nor pleas for salvation directed towards a transcendent Other. They are instead useful and inspiring gestures of humility and respect for the profound nobility and worth of the Triple Gem.
The Pali word vipassana — often translated as "insight" — has a variety of meanings. First, it refers to the flash of liberating intuitive understanding that marks the culmination of Buddhist meditation practice. In the Pali discourses vipassana also refers to the mind's ability to witness clearly as events unfold in the present moment. In this sense it is a skill that a meditator develops using a broad arsenal of meditative tools and techniques. With practice, this skill can bring the meditator to the threshold of liberating insight. In its third meaning, one that has become especially popular in the West in recent years, "Vipassana" (usually with a capital "V") refers to a system of meditation — vipassana bhavana, or "Insight Meditation" — that is based on an interpretation of the Satipatthana Sutta (MN 10), the Buddha's concise "how-to" guide to the development of mindfulness (sati).
Followers of the popular Vipassana movement often cite the Satipatthana Sutta as the essence of the Buddha's teachings; some even claim that the instructions it contains are the only ones necessary for achieving liberating insight. Theravada Buddhism, by contrast, embraces the thousands of discourses of the Pali canon, each highlighting a different aspect of the Buddha's teachings. In Theravada each discourse supports, depends upon, reflects, and informs all the others; even a discourse as important as the Satipatthana Sutta is seen as but a single thread in the Buddha's complex tapestry of teachings.
Although many students do find all they want in Vipassana, some have a nagging sense that something fundamental is missing. This reaction is hardly surprising, as the Satipatthana discourse itself was delivered to a group of relatively advanced students who were already quite experienced and well established in the path of Dhamma practice.
Happily, all those missing pieces can be found in the Pali canon. In the Canon we find the Buddha's teachings on generosity and virtue, the twin pillars upon which all spiritual practice is built. His teachings on the recollection of the Buddha, Dhamma, and Sangha serve to strengthen the development of saddha (faith, confidence), which provides a potent fuel to sustain Dhamma practice long after we return home from that meditation retreat. In the Canon we also find his teachings on the drawbacks of sensuality and the value of renunciation; on developing all the factors in the Eightfold Path, including those that are seldom explored during organized Vipassana retreats: right speech, right livelihood, right effort, and right concentration (meaning jhana). And there is much, much more.
In Theravada, the path to liberating insight does not boil down to a single meditation technique or to being continuously mindful. The path to Awakening is full of surprising twists and turns but, thankfully, the Buddha left for us an assortment of tools to use and skills to learn to help us safely make the journey.
See also: "What is Theravada Buddhism?"
According to Buddhist cosmology, when a living being passes away he or she is reborn into one of thirty-one distinct "planes" or "realms" of existence, of which the human realm is just one. An increase in the human population simply implies that creatures from other planes are being reborn into the human realm at a rate faster than humans are dying. Likewise, a decline in the human population would imply that humans, upon death, are taking rebirth in other planes (or exiting samsara altogether) at a rate faster than other creatures are taking rebirth as humans. These sorts of population shifts have been occurring for countless eons and in themselves hold little cosmic significance.
Nowhere in the Pali canon does Buddha categorically declare, without qualification, "There is no self." Any question that begins along the lines of, "If there's no self..." is thus inherently misleading, dooming the questioner to a hopeless tangle of confusion — "a thicket of [wrong] views" [MN 2]. Such questions are best put aside altogether in favor of more fruitful lines of questioning.
The Pali word "sangha" literally means "group" or "congregation," but when it is used in the suttas, the word usually refers to one of two very specific kinds of groups: either the community of Buddhist monastics (bhikkhus and bhikkhunis), or the community of people who have attained at least the first stage of Awakening. In recent decades, a new usage of the word has emerged in the West, one that seems to have no basis in classical Theravada Buddhist teachings: the usage of the word "sangha" to describe a meditation group or any sort of spiritual community. It sounds innocent enough, but this particular usage can — and often does — lead to profound confusion concerning one of the most fundamental underpinnings of the Buddha's teachings, the going for refuge in the Triple Gem.
The act of going for refuge in the Buddha, Dhamma, and Sangha marks a major turning point in one's spiritual development, the real start of the journey down the Buddhist path. It helps foster a healthy attitude towards Buddhist practice by encouraging the development of right view, and serves as a constant reminder both of the goal of practice and of the means to achieve that goal. It is therefore crucial to be clear and precise about the meaning of the refuges, lest we end up heading down a road quite different from the one the Buddha had in mind.
In taking refuge in the Sangha, we set our inner sights on the ideal community of Noble Ones (ariya-sangha) — those monks, nuns, laywomen, and laymen who, throughout history, have by their own diligent efforts successfully carried out the Buddha's instructions and gained at least a glimpse of the supreme happiness of nibbana. If this is the direction in which we also wish to go, then it is to these individuals that we should turn for refuge:
The Sangha of the Blessed One's disciples who have practiced well... who have practiced straight-forwardly... who have practiced methodically... who have practiced masterfully — in other words, the four types [of noble disciples] when taken as pairs, the eight when taken as individual types — they are the Sangha of the Blessed One's disciples: worthy of gifts, worthy of hospitality, worthy of offerings, worthy of respect, the incomparable field of merit for the world.
— AN 11.12
But going for refuge doesn't stop there. We are also asked to turn to the monastic community (bhikkhu-sangha) for refuge, for it is thanks to the unbroken lineage of this 2,600-year-old institution that we are fortunate enough today to be able to hear the teachings. Moreover, the living example of the monastic community serves to remind us of the immense value of generosity, of living a morally upright life, of renunciation — in short, it reminds us that it is indeed possible to live a life fully in tune with every aspect of the Buddha's teachings. In reality, of course, not every monk or nun necessarily lives up to the Buddha's high standards of conduct. For this reason it is to the institution of the Sangha that we turn to refuge, not to the individual members themselves. This is the Sangha to which lay people have turned since the time of the Buddha:
I go to Master Gotama for refuge, to the Dhamma, and to the Sangha of monks. May Master Gotama remember me as a lay follower who has gone to him for refuge, from this day forward, for life.
So it is these exceptional groups of people — the ariya-sangha and the bhikkhu-sangha — that define the Third Gem and Refuge; it is to these groups that we are asked to turn for refuge, not to some vaguely defined community of like-minded Dhamma friends and fellow meditators. In which group would you rather put your trust?
In an effort to resolve this confusion, some writers have proposed various alternatives to the word "sangha" to describe gatherings and communities of Dhamma companions. But this still leaves me wondering why we must invoke the Pali language here at all. Does a meditation group really need a special name? Why not simply call it a "meditation group" and leave it at that?
"Sangha" is an important term with a rich and precise meaning. It stands for something truly extraordinary and brilliant that can constantly remind us of the highest and most excellent possibilities the Path has to offer. Let's use it well.
The attainment of arahantship and Buddha-hood are identical: the attainment of the Deathless (Nibbana) and the complete and irreversible eradication of the defilements, the underlying cause of suffering. It is the Buddha who (re-)discovers the Dhamma on his own; it is the arahant who puts his teachings into practice and follows in his footsteps.
Here is the Buddha's answer to this very question:
[The Buddha:] "So what difference, what distinction, what distinguishing factor is there between one rightly self-awakened and a monk discernment-released?"
[A group of monks:] "For us, lord, the teachings have the Blessed One as their root, their guide, & their arbitrator. It would be good if the Blessed One himself would explicate the meaning of this statement. Having heard it from the Blessed One, the monks will remember it."
"In that case, monks, listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said, "The Tathagata — the worthy one, the rightly self-awakened one — is the one who gives rise to the path (previously) unarisen, who engenders the path (previously) unengendered, who points out the path (previously) not pointed out. He knows the path, is expert in the path, is adept at the path. And his disciples now keep following the path and afterwards become endowed with the path.
"This is the difference, this the distinction, this the distinguishing between one rightly self-awakened and a monk discernment-released."
— SN 22.58
According to Theravada tradition, many Buddhas have come and gone over countless eons. Every once in a great while, after a long period of spiritual darkness blankets the world, an individual is eventually born who, through his own efforts, rediscovers the long-forgotten path to Awakening and liberates himself once and for all from the long round of rebirth, thereby becoming an arahant ("worthy one," one who has fully realized Awakening). If such a being lacks the requisite development of the paramis (perfections of character), he is unable to articulate his discovery to others and is known as a "Silent" or "Private" Buddha (paccekabuddha). If, however, his paramis are fully developed, he is able to deliver his message (sasana) to the world and is called, simply, a Buddha.
Some of a Buddha's followers may themselves become arahants, but they are not Buddhas, because they required a Buddha to show them the way to Awakening. (All Buddhas and paccekabuddhas are arahants, but not all arahants are Buddhas or paccekabuddhas) No matter how far and wide the sasana spreads, sooner or later it succumbs to the inexorable law of anicca (impermanence), and fades from memory. The world descends again into darkness, and the eons-long cycle repeats.
The next Buddha due to appear is said to be Maitreya (Skt; Pali: Metteyya), a bodhisatta currently residing in the Tusita heavens. Legend has it that at some time in the far distant future, once the teachings of the current Buddha have long been forgotten, he will be reborn as a human being, rediscover the Four Noble Truths, and teach the Noble Eightfold Path once again. Although he plays an important role in some Mahayana Buddhist traditions, whose followers appeal to him for favorable rebirth and salvation, he plays an insignificant role in Theravada. I believe he's mentioned only once in the entire Tipitaka, in the Cakkavatti-Sihanada Sutta (DN 26; The Lion's Roar on the Turning of the Wheel):
[The Buddha:] And in that time of the people with an eighty-thousand-year life-span, there will arise in the world a Blessed Lord, an arahant fully enlightened Buddha named Metteyya, endowed with wisdom and conduct, a Well-farer, Knower of the worlds, incomparable Trainer of men to be tamed, Teacher of gods and humans, enlightened and blessed, just as I am now.
— The Long Discourses of the Buddha (formerly Thus Have I Heard), Maurice Walshe, trans. (Boston: Wisdom Publications, 1987), p 403f.
That jolly fellow with the large belly who appears in Chinese and Japanese art — and whose image adorns countless lawns and living rooms in the West — is Budai (Hotei), a Boddhisatta often identified as Maitreya from a previous lifetime. 
Are you sure there aren't any meditation groups or centers nearby? Even in areas dominated by other religious traditions there may be a few other people quietly and inconspicuously practicing Dhamma by themselves. With a little patient detective work you may be able to find them (see "How can I find other people with whom to study Dhamma and practice meditation?," above).
But if you really are alone, don't despair. Although having a supportive community of like-minded Dhamma friends can be a tremendous boon to your practice, you can still make headway on your own:
Even if you don't have a community of friends, you can still learn to ask yourself good questions — questions that will propel you deeper in your understanding of Dhamma (see "Questions of Skill"). Who was the Buddha? What did he accomplish? What is the goal of Buddhist practice? What is enlightenment? Why is morality the foundation of the Buddha's teachings? What is the purpose of meditation? What is wisdom? Am I honestly following the path that the Buddha laid out? What is the role of faith? If you can keep questions like these alive in your heart, you're bound to stay on track.
It begins with one deceptively simple act: making the inner commitment to "take refuge" in the Triple Gem, to accept the Buddha, Dhamma, and Sangha as your source of spiritual guidance. This act is what makes one nominally "Buddhist." But going for refuge also implies a willingness — if only provisional, at first — to accept the cornerstone of the Buddha's teachings: the law of kamma. According to this universal principle, if you act unskillfully and make poor ethical choices, you are bound to suffer the consequences; if you choose wisely and act in line with the noblest ideals, you stand to benefit accordingly. In other words, your happiness ultimately depends on the quality of your choices and actions; you alone are responsible for your happiness. Your first act after seeking refuge should therefore be to resolve to observe the five precepts — the five basic principles of living that can help prevent you from making grossly unskillful choices. This is where the practice of Buddhism begins.
You don't need a formal public ceremony or "initiation" to make any of this official. There are no equivalents in Buddhism to Christianity's "baptism" or "confirmation" rituals. You don't have to dress differently or wear a badge that says, "I am now a Buddhist." The practice of the Dhamma is a private matter and no one needs to know about it but you. Many Buddhists do, however, find it invaluable to renew their commitment to the Triple Gem and to the precepts from time to time in a more formal way, enlisting the help of a good friend, a respected meditation teacher, or a member of the monastic community (Sangha) as a witness. Administering the refuges and precepts to laypeople is a duty that Buddhist monks are glad to perform.
Many people find it difficult to sustain their commitment to the Dhamma on their own, without the support of like-minded friends and companions. (It can be hard to stick to the precepts if you're surrounded by people who see no harm in telling lies, or in having a secret romantic affair now and then, or in going out drinking all night.) You may have to do a little patient detective work to find this kind of support (see How can I find other people with whom to study Dhamma and practice meditation?, above).
Having taken these first steps, you can proceed along the Buddhist path in your own way and at your own pace. Although you can learn a great deal about Dhamma on your own, your understanding will grow by leaps and bounds once you find a good teacher — someone whom you trust and respect, who keeps to the precepts, and who understands the Dhamma and can communicate it clearly. Other aids to progress in understanding the Dhamma are these: deepening your understanding of the precepts; studying the suttas; getting to know monks or nuns (the Sangha) and becoming acquainted with their traditions; developing a keen, discerning ear that can recognize which of today's popular spiritual teachings actually ring true to what the Buddha taught; and learning meditation. How you proceed is entirely up to you, but the bottom line is this: learn what the Buddha taught and put it into practice in your life as best you can.
If you ever decide that the Buddha's teachings aren't for you, you are free to walk away at any time and find your own way. There is no ceremony for renouncing the Buddha's teachings. Just remember: your happiness is in your own hands.
See also: "Lay Buddhist Practice" in the General Index
In the world of Theravada Buddhism marriage is regarded as a civil contract, not as a spiritual or religious union. Thus there is no standard Buddhist liturgy for marriage. You may simply include whatever texts or passages you and your spouse-to-be find inspiring.
A wedding is an excellent time to formally renew your commitment to both the Triple Gem and the five precepts. In Buddhist countries a couple might pay a visit to the local monastery shortly before or after their wedding to offer food to the monastic community, recite the refuges and precepts in a formal way, receive a little Dhamma instruction, and possibly receive a blessing or two from the monks. If such a visit isn't possible for you, you might put together your own refuges and precepts ceremony (use the formal ceremony as a guide). You might also consider reciting the "Five Subjects for Frequent Recollection," the Maha-mangala Sutta, or any other passages that inspire you.
In Theravada Buddhism divorce (like marriage) is regarded as a civil matter, rather than a religious or spiritual one. I don't know of any suttas in which the Buddha expresses an opinion about divorce. The Buddha did, however, have some suggestions about how a couple should behave while they are married (see DN 31).
For some observations on how divorce is understood in Sri Lanka, see The Position of Women in Buddhism, by Dr. (Mrs.) L.S. Dewaraja. For more about marriage in general, see A Happy Married Life: A Buddhist Perspective, by K. Sri Dhammananda.
From what I've read in the suttas, the Buddha gave no indication that one's sexual orientation or gender identity has any bearing on one's spiritual practice. The five precepts, which form the most basic foundation of a moral life in Buddhism, encourage the abstention from "sexual misconduct," a term that generally refers to sexual activity between two people outside of a long-term committed relationship. It has nothing to do with "orientation."
The Buddha did, however, have strong words to say about sexuality/sensuality in general, as it is one of the most powerful expressions of human craving and attachment. And craving — the second Noble Truth — is a root cause of human suffering. The Buddha was very clear: if you're genuinely concerned about your long-term happiness, then it's worth reflecting deeply on the value of engaging in any activity — be it sexual or non-sexual — that feeds your cravings:
— Iti 109
It is worth noting that the Buddha explicitly discouraged his followers — men and women, alike — from dwelling on their sexual identity (AN 7.48). Although in this particular sutta he was describing heterosexuals, the message clearly applies to us all.
Practicing Buddhists observe the five precepts as a foundation for the moral life that spiritual progress requires. The first of these precepts is to "refrain from destroying living creatures." Because Theravada Buddhism regards human life as beginning at the moment of conception, killing a fetus implies killing a human being, making abortion patently incompatible with the first precept.
One indication of the seriousness with which the Buddha regarded abortion is found in the Vinaya, the collection of texts that define the conduct and duties of Buddhist monastics. According to the Vinaya, if a bhikkhu or bhikkhuni should facilitate an abortion, or if a woman should get an abortion based on their recommendation, then that bhikkhu or bhikkhuni is immediately expelled from the Sangha, having broken one of the four cardinal rules of monastic conduct.
— Pr 3
The word-commentary to this rule makes clear that abortion counts as "intentionally depriving a human being of life." See The Buddhist Monastic Code, Vol. I
The Buddha's advice to parents is straightforward: help your children become generous, virtuous, responsible, skilled, and self-sufficient adults [see DN 31 and Sn 2.4]. Teaching Buddhism to one's children does not mean giving them long lectures about dependent co-arising, or forcing them to memorize the Buddha's lists of the eightfold this, the ten such-and-suches, the seventeen so-and-sos. It simply means giving them the basic skills they'll need in order to find true happiness. The rest will take care of itself.
The single most important lesson parents can convey to their children is that every action has consequences. Each moment presents us with an opportunity, and it is up to us to choose how we want to think, speak, or act. It is these choices that eventually determine our happiness. This is the essence of kamma, the basic law of cause and effect that underlies the Dhamma. It also happens to be the message behind one of the few recorded teachings the Buddha gave to his only child, Rahula. This sutta — the Ambalatthikarahulovada Sutta (MN 61) — offers parents some important clues about teaching Dhamma to young children — in terms of both the content of what to teach and the method to use.
In this sutta the Buddha reprimands the seven year old Rahula for telling a small lie. The content of the Buddha's lesson here is clear and simple: it concerns right speech, and helping Rahula keep himself true to the fundamental principles of virtue. There are several noteworthy aspects to the Buddha's method. First, by artfully drawing comparisons to an everyday utensil (in this case, a water dipper), the Buddha makes his point in vivid and age-appropriate language that Rahula can easily understand. Second, the Buddha doesn't launch into a long-winded abstract lecture on the nature of kamma, but instead keeps the lesson focused on the immediate issue at hand: choosing your actions carefully. Third, although the