Congress regulates the timing of its activities, both from day to day and over the two-year term for which it is elected, by rules governing how its sessions begin, continue, and end. These rules have a variety of procedural consequences, both for the flow of business in each chamber (such as for the or der of business and the consideration of measures) and for actions that involve relations between the chambers and with the executive branch (such as pocket vetoes and recess appointments). The purpose of this report is to describe the main features of the rules governing sessions of Congress, the means by which each chamber implements them, and their chief implications for the conduct of business. Some of the pertinent regulations governing the timing of actions are prescribed by the Constitution, while others are established by the adopted rules of each chamber. Both kinds of regulation have come to be implemented in ways that depend not only on their explicit terms, but also on interpretations that have become accepted and practices that have become customary. The basic terms this report uses to describe the timing of congressional activity are the session, adjournment, and recess. All three terms are used in relation both to the daily and the annual activities of Congress. While they are used in ways that are generally parallel in the daily and annual contexts, their precise meanings often differ in detail. This report will generally distinguish the two contexts, as appropriate, by speaking of "daily" sessions, adjournments, and recesses, and "annual" ones. In either a daily or an annual context, generally speaking, a session is a period when a chamber is formally assembled as a body and can, in principle, engage in business. A session begins when a chamber convenes , or assembles, and ends when it adjourns . In the period between convening and adjournment, the chamber is said to be "in session." Once a chamber adjourns, it may be said to "stand adjourned," and until it reconvenes, it may be said to be "out of session," or "in adjournment." The period from a chamber's adjournment until its next convening is also often called "an adjournment." The term recess , by contrast, is generally used to refer to a temporary suspension of a session, or a break within a session. For a break within the daily session, this term is a formal designation; for a break within an annual session, the term is only colloquial, but is in general use. In either context, a recess begins when the chamber recesses, or "goes into recess." For most purposes, it can be said that a recess, like an adjournment, ends when the chamber reconvenes. During the period between recessing and reconvening, the chamber is said to be "in recess" or to "stand in recess." When a chamber reconvenes from a recess, the suspended session resumes. For some purposes, nevertheless, it can be convenient to speak of a period between convening and recessing, or between reconvening and adjourning, or between recesses, also as "a session." Although these basic explanations of the terms reflect common usage in the congressional context, they do not always take full account of the technical meanings that each term may bear in connection with specific chamber rules and precedents or with various interpretations of provisions of the Constitution. These technical meanings, moreover, may also vary from one formal context to another, or between the House and Senate. It is the intent of this report, throughout, to identify and distinguish the various senses, both formal and informal, in which the respective terms are being used. This report first describes how pertinent rules and practices regulate the daily sessions of Congress and their adjournments and recesses, including discussion of the "legislative day." It then develops a corresponding discussion for the annual sessions of Congress, which addresses, among other things, the use of "pro forma sessions." The report clarifies certain situations in which terms may simultaneously apply in different ways in relation to the daily session and to the annual session. Finally, the report notes some of the most important implications of the occurrence of sessions, adjournments, and recesses in relation to such matters as presidential action on legislation, recess appointments by the President, the operation of statutory expedited procedures ("fast track" procedures), and "lame duck" (post-election) sessions. In context of the daily activities of Congress, each chamber convenes, or assembles, by being called to order by the chair; it is then commonly said to be "in session." Once a daily session is convened, a chamber remains in session, in this sense, until it adjourns for the day (or perhaps until it recesses for the day, although, as elaborated later, the formal effect of recessing is in some respects different). Generally speaking, it is only when the chamber is in session in this sense that it can engage in official business. When a chamber is in session, in this sense, a presiding officer will be in the chair, Members may be present in their official capacities and participate in acts of the body, and the presence of a quorum may be required. In particular circumstances, however, either chamber may provide that, during a specific daily session, no business, or none of specified kinds, may occur. In these terms, the period between the convening of a daily session and its adjournment or recess is necessarily a continuous period of time. Normally, on any day on which a chamber convenes, it adjourns (or recesses for the day) later on the same day. A calendar day on which a chamber convenes and then adjourns or recesses until a later calendar day may be called a "calendar day of session" or, more informally, simply a "day of session" for that chamber. In some Senate contexts, the term "session day" is used in a technical sense, especially, as described later, in connection with expedited or "fast track" procedures. The House, on the other hand, makes no use of this term in formal contexts. It sometimes happens that a chamber convenes on one day and remains continuously in session, without adjourning or recessing, until the next calendar day (or even until some later day). Whether it might be appropriate to describe such a period as a single "day of session" or two (or more) could depend on the specific procedural context. If, on the other hand, a chamber were to be out of session at all points throughout an entire calendar day, it could not, in general, be appropriate to speak of that day as a "day of session" for that chamber. An adjournment of the daily session of either chamber, more formally called an adjournment from day to day , terminates that daily session. More technically, an adjournment from day to day terminates a "legislative day," a concept that is more fully addressed below in the section on " Relation of "Days of Session" and Legislative Days ." A chamber normally adjourns its daily session by adopting a motion to adjourn. The Senate sometimes adjourns, instead, by agreement to a unanimous consent request. In the practice of the House, however, adjournment by unanimous consent occurs only by declaration of the Speaker, and only "when no Member is available" to offer the motion. The Senate also may adjourn pursuant to a previous order setting the time at which adjournment will occur; the House generally does not use such a practice. Finally, Senate rules authorize the chair to declare a daily adjournment of the Senate if notified of an "imminent threat." Once a chamber adjourns, it is "in adjournment." At that point, no daily session is in progress, which means, in general, that the chamber cannot conduct any official business as a body. A chamber may, however, adopt orders (while it is in session) providing that certain kinds of administrative business, such as the receipt of messages from the President or reports of committees, may occur during an adjournment. When a chamber reconvenes after a daily adjournment, a new daily session begins. At that point, the daily order of business prescribed by chamber rules begins anew. In each chamber, for example, a new calendar day of session begins with a prayer by the Chaplain and the recitation of the Pledge of Allegiance. Any legislation that was under consideration and pending at the adjournment of the previous day's session is converted into the unfinished business of the new daily session. During a daily session, either chamber may (by motion, resolution, or unanimous consent) adopt an order setting the time when it will reconvene after it adjourns. If a chamber adjourns its daily session in the absence of such an order, it reconvenes in accordance with a resolution specifying the normal schedule of the chamber that it typically adopts at the beginning of each new Congress. In addition to a daily adjournment, which terminates a daily session, a chamber may take a recess within its daily session. For example, a chamber may recess while awaiting the arrival of a specific item of business, or in order to convene in a joint meeting with the other chamber to hear an address by a foreign dignitary. Unlike a daily adjournment, a recess of the daily session does not terminate the daily session. Instead, when a chamber reconvenes after a recess, the same daily session resumes, and business continues from the point it had reached when the recess began. A recess often occupies only a brief period during a day's session. A chamber, however, also may recess its daily session overnight or for a longer period.