The two main door types are interior and exterior. Exterior doors will provide a weathertight seal when closed and should maintain a certain thermal insulation value of the walls in which they reside. Interior doors offer access from room to room while providing privacy as well. It’s not uncommon to see exterior doors utilized in interior construction. Construction of doors should follow certain building codes such as fire-resistance, emergency egress, safety glazing, etc. Most door units are prebuilt in the factory with standard sizes per manufacturer which correspond to rough opening sizes. Because of the pre-built ‘unit’ style, sizes and locations should be pre-planned with shop drawings and/or door schedules to assure rough opening and lintel sizes are correct. 
         Doors can be made of steel, aluminum, wood, stainless steel, glass, plastics, fiberglass, among other materials. Another categorization for doors is their operation mode such as:
Double Swinging
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Pocket Sliding
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Bypass SLiding
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Surface Sliding
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Rolling or Coiling
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Some door features and accessories might include glazing, grilles, louvers, weatherstripping, molding, trim, mullions, transoms. Some specialty doors that may be utilized are sound reduction, lead-lined, etc.
Priming or even complete prefinishing of doors with paint, stain, varnishes, lacquers, or other coatings has become quite popular because of the time savings, cost savings, and reduced project cleanup they offer. But site finishing of doors after installation is still a common practice. Pre-Machining, which is the fabrication of holes and recesses to receive hardware, has become very popular as well as it increases effeciency, ease of installation, and reduces costly/timely skilled field labor to prepare the door. Factory machining preps the door to receive mortise, cylindrical, tubular, unit, and rim locks. Beveled edges, hinge recess, etc may also be pre-machined. Like any prebuilt construction aspect, pre-machine requires planning, shop drawings, hardware schedules, template exchanging, etc to be successful.
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If a door will be prefinished, it should also be pre-machined if possible to reduce the need for damaging the finish while field machining for the door hardware.
          Doors will swing one of the following 4 directions (from the approach side): Left Hand, Right hand, Left-Hand Reverse Bevel, Right-Hand reverse Bevel.
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The rough opening is what the door is placed in, is often slightly larger than the frame itself, and often drives how doors are sized when being sold. A door can be flush with the wall it’s going into, be recessed, or protrude slightly. The head is the uppermost horizontal member of the frame. The jamb is the vertical side members of the frame. The stop is the part of a door frame that runs vertical near the hinge and projects out against which the door closes. The casing conceals the frame to wall joint at the jambs/heads. The threshold is the doorway sill utilized primarily to conceal flooring material joints and provide another stop surface for the door (ad providing weather protection at an exterior door).        
             A door must be fit to a rough opening, placed in the rough opening, plumbed, leveled, and shimmed just right before it is ultimately secured to the wall. If a door is prehung it may be placed as one complete unit (frame and slab or leaf) into the opening. Otherwise the frame is placed first by itself to later recieve the door slab. Once the frame is in precise position, it is often secured with the appropriate fastener through the jambs and header, into the wood, masonry, or metal wall framing adjacent to it. At that point the door is often checked again that it’s positioning was maintained properly during fastening. If not prehung, the door is then placed on the hinges and secured.  
After a door is installed (if they’re not in place already) door hardware components will need to be secured permanently to the door. These components might consist of any combination of the following: Lockset with latches, bolts, cylinder and stop; Hinges; Closers; Panic Hardware; Push and Pull Bars & Plates; Kick Plates; Door Stops, Holders, and Bumpers; Thresholds; Weatherstripping; Door Tracks and/or guides.
Factors regarding hardware selection include: recessed or surface mounted items, function, operation ease, material, finish, texture, color, durability with respect to expected usage, exposure to weather, etc.  
                The two most common types of doors found is residential and commercial construction are Hollow-Metal Doors & Frames and Wood Doors and Frames which are discussed at length in other articles.