Terms
Dating is a non-committed romantic relationship that has no promise of ending in marriage. There are liberal and conservative forms of dating ranging from what could be called "Recreational Dating" where relationships often physical in nature and are easily broken up to pursue other partners, to a "Christian Dating" that emphasizes physical purity and respect of the other boyfriend or girlfriend.
Term: Courtship
Courtship is most commonly defined as a trial relationship between the friendship state and a commitment to marriage. Courting means "to woo, to solicit, to seek, to flatter." (Websters 1828) This is where the young man tries to win the heart (romantic emotions) of the young woman. If successful, the young man then usually asks the young woman for her hand in marriage. Courtship also has varying shades in terms of practice. Some people mean little more that that they are dating, while others imply that they are intending to get marriage. Most often courtship includes some kind of parental involvement, at least in terms of approving of the relationship. There is often accountability and seldom are the young adults allowed to go on dates unchaperoned. There is usually an expectation with courtship that this relationship is headed toward marriage, but there has been no covenant made to assure this.
Term: Betrothal (Espousal)
Be "troth" al. The root word "troth" comes from the old English word meaning, "truth." In old English wedding ceremonies, the young man would say to the young woman, "to thee, I plight (or pledge) my troth." The young man was saying to his bride that he was pledging his loyalty, faithfulness, fidelity and devotion, for as long as they both would live. Betrothal is an absolute covenant commitment to marriage. In Biblical days, a betrothal was seen as being as binding as the wedding vows themselves and could only be broken by a divorce (see the example of Joseph & Mary -- Matthew 1:18-19) and solely for the only scriptural reason given for divorce...marital unfaithfulness (Deut. 22:23-24, Matt. 5:32, Matt. 19:9). A betrothal is usually only entered into with the blessing of both sets of parents (at least the Scripture only indicates this perspective) and is a preparation time for the wedding and marriage. The Church (commonly called the Bride of Christ) is in a betrothal with Christ, awaiting his return to earth where he will take his bride to live with him in the home he had prepared. (John 14:2-3). While the wedding has not yet occurred (this will take place at the marriage supper of the Lamb, see Revelation 19:7-9), it is appropriate to call a betrothed woman a "bride" just as the Bible speaks of Mary as Joseph's "espoused wife" before they were married (Luke 2:5-KJV). Betrothal is similar to a modern day engagement, but with a definite covenant commitment to marriage, not be broken off as many modern engagements are.