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]

There was a renewed interest in handcrafted art and design following the industrial revolution. This became the “Arts and Crafts” era and paved the way for the Craftsman home, or “arts and crafts” home.

Craftsman homes focus on simplicity to counter the ornate stylings of Victorian homes. They’re also designed to highlight the craftsmanship of its builders and include:

• A low-pitched roof with overhanging eaves
• A covered porch
• Woodwork including exposed beams and built-in features like shelving
• Natural tones to complement the warmth from woodworking

Craftsman homes are favored for their character and are another versatile style that may borrow common elements from other home styles.

The United States has 63 national parks, which are Congressionally-designated protected areas operated by the National Park Service, an agency of the Department of the Interior.[1] National parks are designated for their natural beauty, unique geological features, diverse ecosystems, and recreational opportunities. While legislatively all units of the National Park System are considered equal with the same mission, national parks are generally larger and more of a destination, and hunting and extractive activities are prohibited.[2] National monuments, on the other hand, are also frequently protected for their historical or archaeological significance. Eight national parks (including six in Alaska) are paired with a national preserve, areas with different levels of protection that are administered together but considered separate units and whose areas are not included in the figures below. The 423 units of the National Park System can be broadly referred to as national parks, but most have other formal designations.[3]

A bill creating the first national park, Yellowstone, was signed into law by President Ulysses S. Grant in 1872, followed by Mackinac National Park in 1875 (decommissioned in 1895), and then Rock Creek Park (later merged into National Capital Parks), Sequoia and Yosemite in 1890. The Organic Act of 1916 created the National Park Service "to conserve the scenery and the natural and historic objects and wildlife therein, and to provide for the enjoyment of the same in such manner and by such means as will leave them unimpaired for the enjoyment of future generations."[4] Many current national parks had been previously protected as national monuments by the president under the Antiquities Act or as other designations created by Congress before being redesignated by Congress; the newest national park is New River Gorge, previously a National River, and the most recent entirely new park is National Park of American Samoa. A few former national parks are no longer designated as such, or have been disbanded. Fourteen national parks are designated UNESCO World Heritage Sites (WHS),[5] and 21 national parks are named UNESCO Biosphere Reserves (BR),[6] with eight national parks in both programs.

Thirty states have national parks, as do the territories of American Samoa and the U.S. Virgin Islands. The state with the most national parks is California with nine, followed by Alaska with eight, Utah with five, and Colorado with four. The largest national park is Wrangell–St. Elias in Alaska: at over 8 million acres (32,375 km2), it is larger than each of the nine smallest states. The next three largest parks are also in Alaska. The smallest park is Gateway Arch National Park, Missouri, at 192.83 acres (0.7804 km2). The total area protected by national parks is approximately 52.2 million acres (211,000 km2), for an average of 829 thousand acres (3,350 km2) but a median of only 208 thousand acres (840 km2).[7]

The national parks set a visitation record in 2017, with more than 84 million visitors and set a further record in 2018 with a 0.1% increase.[8][9] Great Smoky Mountains National Park in North Carolina and Tennessee has been the most-visited park since 1944,[10] and had over 14 million visitors in 2021.[11] In contrast, only about 7,000 people visited the remote Gates of the Arctic National Park and Preserve in Alaska in 2021.

1. From this valley they say you are going, I will miss your bright eyes and sweet smile, For they say you are taking the sunshine, that brightens our pathways awhile. (CHORUS) Come and sit by my side if you love me, do not hasten to bid me a-dieu, but remember the Red River Valley, and the cowboy who loved you so true.

2. I’ve been thinking a long time, my darlin’, Of the sweet words you never would say, now, alas, all my fond hopes must vanish. For they say you are going away. Repeat Chorus: Come and sit by my side if you love me, do not hasten to bid me a-dieu, but remember the Red River Valley, and the cowboy who loved you so true.

3. Do you think of the valley you’re leaving? Oh, how lonely and sad it will be! Do you think of the kind hearts you’re breaking, and the pain you are causing to me? Repeat Chorus: Come and sit by my side if you love me, do not hasten to bid me a-dieu, but remember the Red River Valley, and the cowboy who loved you so true.

4. I have promised you, darlin’, that never, will a word from my lips cause you pain; And my life, it will be yours forever If you only will love me again. Repeat Chorus: Come and sit by my side if you love me, do not hasten to bid me a-dieu, but remember the Red River Valley, and the cowboy who loved you so true.

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.

The Parthenon in Centennial Park, in Nashville, Tennessee, is a full-scale replica of the original Parthenon in Athens. It was designed by architect William Crawford Smith and built in 1897 as part of the Tennessee Centennial Exposition.

Today the Parthenon, which functions as an art museum, stands as the centerpiece of Centennial Park, a large public park just west of downtown Nashville. Alan LeQuire's 1990 re-creation of the Athena Parthenos statue in the naos (the east room of the main hall) is the focus of the Parthenon just as it was in ancient Greece. Since the building is complete and its decorations were polychromed (painted in colors) as close to the presumed original as possible, this replica of the original Parthenon in Athens serves as a monument to what is considered the pinnacle of classical architecture. The plaster replicas of the Parthenon Marbles found in the Treasury Room (the west room of the main hall) are direct casts of the original sculptures which adorned the pediments of the Athenian Parthenon, dating back to 438 BC. The surviving originals are housed in the British Museum in London and at the Acropolis Museum in Athens.

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.

Queen Anne homes were popularized in the later Victorian era, beginning around 1880. This style is the quintessential Victorian home for many, with ornate woodworking and decor inside and out.

Queen Anne homes have key regional differences across the country, but maintain these essentials:

• Textured walls with decorative shingles or half-timbering
• Large round or polygonal tower at the home’s corner
• Steeply pitched and asymmetrical roof
• Decorative spindles on porches and trim
• Decorative single-pane or stained glass windows

Queen Anne architecture is most common in homes, but can also be seen in schools, churches, and office buildings.

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.

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.”