American popular music has had a profound effect on music across the world. The country has seen the rise of popular styles that have had a significant influence on global culture, including ragtime, blues, jazz, swing, rock, bluegrass, country, R&B, doo wop, gospel, soul, funk, punk, disco, house, techno, salsa, grunge and hip hop. In addition, the American music industry is quite diverse, supporting a number of regional styles such as zydeco, klezmer and slack-key.

Distinctive styles of American popular music emerged early in the 19th century, and in the 20th century the American music industry developed a series of new forms of music, using elements of blues and other genres of American folk music. These popular styles included country, R&B, jazz and rock. The 1960s and 1970s saw a number of important changes in American popular music, including the development of a number of new styles, such as heavy metal, punk, soul, and hip hop. Though these styles were not in the sense of mainstream, they were commercially recorded and are thus examples of popular music as opposed to folk or classical music.

Cape Cod homes are similar to the British or American Colonial homes, though they originated further north in Cape Cod, Massachusetts. These are often seen as the classic American family home since the style’s revival in the 20th Century.

Cape Cod homes are identified by their:

• Shingle exteriors
• Modest size and ornamentation compared to British Colonial homes
• Originally single-story homes
• Large central fireplaces
• Attic lofts (20th-century revival)
• Dormer windows (20th-century revival)

Cape Cod homes are built of local wood and stone to withstand the north-eastern weather. This exterior weathering provides an iconic weathered-blue color to these homes.

Townhomes are common in cities and densely populated neighborhoods. Townhouses are tall and narrow homes designed to make the most out of vertical space without too much of a yard or garden area.

Homes are considered townhouses when they:

• Share one or two walls with adjacent homes
• Have their own entrances
• Are built with multiple floors to maximize vertical space
• Often share a similar style to their neighbors’ homes and may operate under an HOA

Townhouses can be built to mimic other architecture styles, like Italianate and Greek Revival, while maintaining the condensed, vertical floor plan.

Second Empire homes were a modern Victorian-era style that started in France before spreading through the Northeastern and Midwestern United States. Second Empire architecture features similar ornate Victorian trends, though generally offers a simplified Victorian aesthetic.

These elements help identify a Second Empire home:

• Uniquely shaped Mansard Roof
• Decorative window framing and dormers
• Decorative rails or balustrades around terraces and staircases
• Iron roof crest and eaves with support brackets

Second Empire homes are also easy to identify since they’re the only Victorian-era style that often features a symmetrical, rectangular floor plan.

Federal-style homes became popular after the American Revolution and were a refined upgrade to the popular Georgian house style. They have the same recurring shape and symmetry as other Colonial house styles, but their delicate ornamentation sets them apart.

Federal Colonial homes often feature:

• A layout built around a central hall
• An elliptical fanlight and two flanking lights (windows) around the door
• Paladin or tripartite windows

The elliptical fanlights and paladin windows are key distinguishing features from Georgian-style homes.

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]

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.

Italianate architecture continues the trend of asymmetrical design, romanticism, and Medieval influence — this time borrowing features from Medieval Italy. Italianate style is common up and down the East Coast and peaked in popularity between 1850 and 1880.

Italianate architecture features:

• Belvederes for natural light and airflow
• Overhanging eaves with decorative support brackets
• Tall and narrow or pedimented windows with rounded crowns
• Cast iron detailing and decor

Pattern books were becoming a popular way for craftsmen to build homes in different styles. This flexibility meant Italianate features were accessible for a variety of homes including large estates and urban townhouses.

Around the 1820s, Americans experienced a renewed interest in classic Greek and Roman culture. This cultural shift was a natural fit for architects, who brought the Greek Revival house style to life.

Greek Revival architecture became popular in homes as well as businesses, banks, and churches. Prominent features include:

• Easy to identify shapes, including a rectangular building and triangular roofs
• Gable-front designs
• Large porches and protected entryways
• Greek-inspired columns both square and round

Greek Revival homes often have decorative trim and moulding around the front door and windows. These ornate features and columns are easy ways to identify Greek Revival architecture.