Reverend is a title often used by members of the Christian clergy.
It is a formal title within mainline Protestant churches (e.g. Very Reverend, Right Reverend) and to a lesser extent within Evangelical churches, usually larger congregations within denominations. In smaller churches it may be used informally.
Within non-denominational or seeker-friendly churches the term is rarely, if ever, used. Churches of Christ do not use the term at all, preferring terms such as minister, evangelist, or preaching elder (where the main preacher is also an elder).