Some researchers argue that divorce rate does not always reflect actual interactions among people; that is, some countries may show a low divorce rate because, in such countries, people rarely get married in the first place.
The term between divorce and remarriage varies depending on the country and the gender of the divorcee. In some countries, women need to wait longer than men before remarrying to avoid confusion about paternity. Children born after divorce may or may not be recognized as children of their father depending on the period between divorce and birth. In most common law jurisdictions there is a presumption that the child born during the marriage is the father's child, however this presumption can be overcome by identifying the putative father and bringing a paternity or affiliation proceeding. If the child was conceived before the divorce but born afterward this is the kind of grey area that jurists enjoy litigating. If a man accepts the child as his own he may be declared the father by estoppel as the parens patrie power of the court would rather the child have a male role model responsible for child support and other parental obligations rather than have the child grow up in a monoparental family.
A man who has been divorced is a divorcé; a divorced woman is a divorcée (from French).
In the 1530s, Henry VIII decided that he wished to divorce his first wife, Catherine of Aragon, on the grounds of affinity; he argued that, since Catherine was his brother Arthur's widow, the marriage had never really existed. Catherine claimed that her marriage to Arthur had never been properly consummated. In 1533Thomas Cranmer was appointed Archbishop of Canterbury and he declared that Henry's marriage to Catherine was void, effectively bastardizing their daughter Mary (later Mary I). In 1536 Cranmer similarly declared Henry's marriage to Anne Boleyn void, most probably due to Henry's pervious relationship with Anne's sister Mary Boleyn. Cranmer tried to reform the Church of England's Canon law so that it allowed divorce for adultery, cruelty, and desertion, but these changes were not implemented.
Following Lord Roos's divorce on the grounds of adultery in 1670, the procedure for divorce in English law went as follows: first the husband brought an action for "criminal conversation" to establish the adultery, then he obtained a divorce a mensa et thoro from the church and then finally he petitioned the House of Lords to grant the divorce.
In 1853 a Royal Commission made recommendations on how to improve the procedure of getting a divorce. In 1857 the Court for Divorce and Matrimonial Causes, based in London, was established, taking over the divorce duties of the church courts. Men could obtain divorce for adultery, but women had to prove cruelty or desertion, in addition of their husband's adultery. In 1923 women were allowed to use the same grounds for divorce as men. In 1969, after much debate, matrimonial breakdown became grounds for divorce.
This change in nomenclature was concomitant with the trend of most states to depart from the more restrictive fault-based divorce to the more liberal no-fault divorce standard.
A number of states have discarded fault-based grounds for divorce, however all 50 states do offer some form of no-fault divorce.
The procedural and substantive specifics of pleading vary among jurisdictions. Examples of fault-based grounds include: adultery, attempted murder, desertion, habitual drunkenness, infection of one’s spouse with venereal disease, insanity, impotency, mental cruelty, physical cruelty, and use of addictive drugs.
Again, the specifics vary among the several states. As a general statement however, a no-fault divorce occurs when neither the wife nor the husband is to blame for the breakdown of the marriage. Common bases for no-fault divorce are incompatibility, irreconcilable differences, and irretrievable breakdown of the marriage. In some jurisdictions, where the parties have lived separately for a statutoraly determined amount of time with the intent of permanent separation, this can constitute no-fault grounds.
The Canada Divorce Act recognizes three grounds for divorce: adultery, cruelty, and being separated for one year. Most divorces proceed on the basis of the spouses being separated for one year, even if there has been cruelty or adultery. This is because proving cruelty or adultery is expensive and time consuming.  The one-year period of separation starts from the time at least one spouse intends to live separate and apart from the other and acts on it. You do not need a piece of paper or a court order to be separated. There is no such thing as a "legal separation" in Canada.  You can be separated even if you are living in the same house. You can apply for the divorce in a province in which you or your spouse has lived for at least one year.
In Japan, under the national laws, divorce is a simple process of submitting a declaration to the relevant government office that says both spouses agree to divorce. Unfortunately for foreign spouses, it is all too easy, and common, for a Japanese spouse to forge a signature on a divorce form. So some countries do not accept this kind of divorce carried out in Japan. As a defense, there is a form you can submit that prevents a divorce form from being submitted for six months.
There are also three other types of divorce in Japan: Divorce by mediation in a family court (chotei rikon), Divorce by judgement of the family court (shimpan rikon), and Divorce by judgment of a district court (saiban rikon).
A more accurate concluding statement to draw from this data would be "The divorce rate is half the marriage rate." The statement "50% of marriages end in divorce" would instead have to study a sample of marriages throughout their duration, that is, over a period of many years, and determine how many of the marriages actually performed ended in divorce (as compared to annulment or death of a spouse). These two statements would be equivalent if (1) marriage and divorce trends did not change over a time period equal to the length of a marriage (say, 50 years), and (2) all divorces were performed in the same country as their marriage. While the second statement is close enough to true, the first one is clearly not, as during the ten year period from 1991 to 2001 the divorce rate decreased from 0.47% to the above stated 0.40%.