
The National Academy of Sciences (NAS) is a United States nonprofit, non-governmental organization. NAS is part of the National Academies of Sciences, Engineering, and Medicine, along with the National Academy of Engineering (NAE) and the National Academy of Medicine (NAM).
As a national academy, new members of the organization are elected annually by current members, based on their distinguished and continuing achievements in original research. Election to the National Academy is one of the highest honors in the scientific field. Members of the National Academy of Sciences serve pro bono as "advisers to the nation" on science, engineering, and medicine. The group holds a congressional charter under Title 36 of the United States Code.
Founded in 1863 as a result of an Act of Congress that was approved by Abraham Lincoln, the NAS is charged with "providing independent, objective advice to the nation on matters related to science and technology. … to provide scientific advice to the government 'whenever called upon' by any government department."[2]
The Academy receives no compensation from the government for its services.[3]
The Academy currently has 2,984 members and international members. Existing members elect new members for life. Up to 120 members are elected every year; up to 30 foreign citizens may be elected as international members annually. The election process begins with a formal nomination, followed by a vetting period, and culminates in a final ballot at the Academy's annual meeting in April each year. Members are affiliated with a section -- a specific scientific field -- in one of six so-called "classes": (1) Physical and Mathematical Sciences; (2) Biological Sciences; (3) Engineering and Applied Sciences; (4) Biomedical Sciences; (5) Behavioral and Social Sciences; and (6) Applied Biological, Agricultural, and Environmental Sciences.[6] Since its founding, the Academy has elected 6,457 members. Harvard University is associated with the most members (329), some 5% of the all-time total. The top ten institutions, half of which are Ivy League universities, account for nearly 28% of all members ever elected.[11]
Top 10 Primary Institutions | Members (1963-2022) |
---|---|
Harvard University | 329 |
Stanford University | 250 |
University of California, Berkeley | 242 |
Massachusetts Institute of Technology | 206 |
Yale University | 132 |
Princeton University | 128 |
California Institute of Technology | 126 |
Columbia University | 125 |
University of Chicago | 120 |
University of Pennsylvania | 83 |
Modern Tudor homes are inspired by Medieval European Tudor homes and often have a charming cottage aesthetic. They’re popular on the East Coast and in parts of the Midwest.
Tudor homes are an easy style to identify. They feature:
- Steeply pitched gable roofs
- Exposed and decorative half-timbering with stucco exterior
- Mixed-material brick or stone walls
- Casement windows in groups or with diamond shapes
The Tudor Revival reached peak popularity in the 1920s and is still widely popular today.
Mid-century Modern designs are nothing new and have influenced interior design, graphic art, and house styles. Mid-century Modern homes are designed to embrace minimalism and nature. They’re also often modeled to appeal to a futuristic or abstract concept.
Mid-century Modern homes can be identified by their:
- Flat planes and clean lines
- Monochromatic brickwork
- Asymmetrical home layouts
- Nature-inspired interior
- Interior level shifts between rooms
Mid-century architecture is still widely popular today, as are Mid-century Modern interior design and furniture trends.
Contemporary homes resemble the modern homes of the mid-20th century with a renewed emphasis on sustainability. Current contemporary styles are rooted in minimalism, which you can see in these key features:
- Asymmetrical exterior
- Clean lines
- Open floor plan layout
- Geometry highlighted in its structure
- Sustainable building materials and features
Contemporary homes aim to find beauty in a simple and appealing design with ties to nature and more warmth than modern home styles offer.
Ranch house styles are the most searched style in the US today and are common in cities and suburbs across the country. There are various ranch house styles, including California and split-level ranch homes. The main distinguishing features between these styles are living space and home layout.
Ranch style homes feature:
- Single-story floor plans with low-pitched roofs
- Rectangular, “U,” or “L” shaped open floor plans
- Patio or deck space connected to the home
- Often includes a finished basement or attached garage
Ranch homes are the most popular homes in 34 US states — particularly in the Midwest and on the East Coast.
Gothic Revival architecture grew in the mid-19th century and was one of the early styles of Victorian-era homes. The Gothic Revival style takes influence from Medieval Europe and was designed as a country home. Architects believed the asymmetrical design and ornamentation complemented the nature of rural America.
Gothic Revival homes can be identified by their:
- Pointed arch in windows, doors, and decoration
- Elaborate wood trim vergeboards and bargeboards
- Steeply pitched roofs and front-facing gables
- Towers and turrets resembling medieval castles
Gothic Revival architecture was a popular style for schools and churches as well as rural homes.
Colonial-style houses are simple rectangular homes that became popular in the 1600s as colonists settled the East Coast. These homes have many variations due to the fact that new communities all over the world built Colonial-style homes to suit their culture.
British Colonial style is the most common and recognizable Colonial home. Its key features include:
- A side-gabled roof
- Two floors
- A centered front door
- Symmetrical windows on either side of the door
The rectangular shape and interest in symmetry are seen in other Colonial house styles, too. Materials and decorative features can vary by region, as some Colonial houses sport brick exteriors and ornate trim, while others showcase shingle siding and simple shutters.
These are also some of the cheapest types of houses to build.


Georgian-style homes were one of the most common styles in the 18th century and showcased formal and classical details that previous homes didn’t. Georgian houses are similar to Federal houses, though they can be distinguished by:
- A crown and pilasters framing the front door
- Decorative quoins or bricks at the corners
- Smooth decorative blocks as moulding
You can also find regional variations with hooded front doors and pent roofs between levels.

Most Dutch Colonial homes you find today are actually from the Colonial Revival period of the early 20th Century. Original Dutch Colonial homes feature flared roof eaves and creative wood and brickwork. They are much more ornamental than classic Colonial homes, though the Dutch Colonial Revival style tends to be more subdued than the original Dutch Colonial homes.
Dutch Colonial Revival houses feature:
- Broad gambrel roofs that are visually similar to barn-style roofs
- Open-floor plans
- Flared roof eaves
- Split doors
The large barn-style roofs are the most identifiable feature of a Dutch Colonial home and even became known as “Dutch roofs.”
Prairie-style homes were made famous by the architect Frank Lloyd Wright. These homes celebrate and complement the natural beauty of the Midwestern landscape with low and long shapes in the floor plan and building elements.
Prairie-style houses showcase:
- Long and low-to-the-ground builds
- Flat or shallow roofs with overhanging eaves
- Thin bricks or stucco exteriors to match the house shape
- Minimalist yet stylized ornamentation
Prairie houses inspired the flat planes and natural elements popular in Mid-century houses.
Mediterranean home styles are made of stucco, so they’re most common in warm climate states like Arizona and California. These homes grew in popularity in the 1920s and ‘30s after being featured as homes for the rich and famous on the silver screen.
Mediterranean-style homes include Spanish and Italian architectural elements. These key features make them easy to spot:
- Stucco walls painted white or brown
- Classic red tile roofs
- Arched doorways and windows
- Ornamentation including wrought iron, heavy doors, and decorative tiles
Mediterranean homes still carry the feelings of class and luxury they were built with over 100 years ago, with an added element of history and charm.