United States Of America

The flag of USAThe U.S. flag has thirteen stripes - red and white. USA had 13 states. The U. S. flag has 50 stars, because there are fifty states in the country.

1. History of America

Christopher ColumbusChristopher Columbus ( 1451 20 May 1506)

Was a navigator, colonizer, and explorer whose voyages across the Atlantic Ocean led to general European awareness of the American continents in the Western Hemisphere.

With his four voyages of exploration and several attempts at establishing a settlement on the island of Hispaniola. Four voyages of Christopher Columbus

Role of Labor in Americas Economy

Until shortly after World War I, most workers were immigrants from Europe, their immediate descendants, or African Americans who were mostly slaves taken from Africa, or slave descendants.

Beginning in the early 20th century, many Latin Americans immigrated; followed by large numbers of Asians following removal of nation-origin based immigration quotas.

The promise of high wages brings many highly skilled workers from around the world to the United States.

Immigration to the United States United States received 4.31 immigrants per 1000 people in 2009, ranking 25th globally.

Nearly 8 million immigrants came to the United States from 2000 to 2005 more than in any other five-year period in the nation's history.

The analysis shows that 31% of adult immigrants have not completed high school. A third lack health insurance.

2. Geographical value of America

Rural and Urban areas of America

Data in figures about Rural and Urban areasToday, 15 percent of the United States' inhabitants live in suburban and urban areas.

but cities occupy only 2 percent of the country.

Rural areas occupy the remaining 98 percent.

U.S. Population Living in Urban vs. Rural Areas 1

Geographic Division:# of AreasTotal PopulationPercent of U.S. TotalTotal U.S. Population285,230,516100Population living in Urban Areas 23,629225,956,06079.219Population living in Rural Areas59,274,45620.781Urban Area Categories:1. Urbanized Areas over 200,000 population153166,215,88958.2742. Urbanized Areas 50,000 - 199,999 population31029,584,62610.3723. Urban Clusters 5,000 - 49,999 population183825,438,2758.9184. Urban Clusters 2,500 - 4,999 population13284,717,2701.654

Great places of America

The Colorado River winds through Nankoweap Canyon in Grand Canyon National Park, Arizona.

Times Square, New York

Statue of Liberty New York City

Golden Gate Bridge, San Francisco

Monument Valley, Arizona/Utah

Science and Technology

Science & Technology of America The United States has been a leader in scientific research and technological innovation since the late 19th century.In 1876, Alexander Graham Bell.

Thomas Edison's the first long-lasting light bulb, viable movie camera.

Nicola Tesla pioneered alternating current, the AC motor, and radio.

The Wright brothers, in 1903, made the first sustained and controlled heavier-than-air powered flight.

The Space Race produced rapid advances in rocketry, materials science, and computers. Neil Armstrong was the first man to set foot on the Moon, on July 20, 1969. more than half of the world's land planted with biotech crops is in the United States.

Neil Armstrong

Neil on Moon

Albert Einstein 14 March 187918 April 1955 A theoretical physicist who is widely regarded as one of the most influential scientists of all time.

Theories of relativity. Relativistic cosmology. Post-Newtonian expansion. Perihelion advance of Mercury. Deflection of light by gravity. etc

Culture of America

ReligionsAccording to the CIA different religions in the United States:

Christians: (78.5%) Protestant (51.3%) Roman Catholic (23.9%) Mormon (1.7%) other Christian (1.6%) unaffiliated (12.1%) none (4%) other or unspecified (2.5%) Jewish (1.7%) Buddhist (0.7%) Muslim (0.1%)

National holidays

DateOfficial NameJanuary 1New Year's DayThird Monday in JanuaryBirthday of Martin Luther King, Jr., or Martin Luther King, Jr. DayJanuary 20, the first January 20 following a Presidential electionInauguration DayThird Monday in FebruaryWashington's BirthdayLast Monday in MayMemorial DayJuly 4Independence DayFirst Monday in SeptemberLabor DaySecond Monday in OctoberColumbus DayNovember 11Veterans DayFourth Thursday in NovemberThanksgiving DayDecember 25Christmas

Common American Foods

Popular Culture of AmericaFashion Music Films Dance Television Theater

Transportation of America

Transportation System of America Everyday personal transportation in America is dominated by the automobile.

As of 2003, there were 759 automobiles per 1,000 Americans, compared to 472 per 1,000 inhabitants of the European Union the following year. About 40% of personal vehicles are vans, SUVs, or light trucks. Southwest Airlines is number one Of the world's thirty busiest passenger airports, sixteenth is the United States.

Transportation System of Americabusiest airport in the world, Hartsfield-Jackson Atlanta International Airport.

While transport of goods by rail is extensive, relatively few people use rail to travel, within or between cities. Only 9% of total U.S. work trips use mass transit, compared to 38.8% in Europe

U.S Sports and Entertainment

Sports of America Baseball American Football Basketball Ice hockey Soccer

Rugby or Football

Base ball

USA Basketball Team

Ice Hockey Stadium

Soccer

Entertainment in America Hollywood movies are providing great entertainment not only to the U.S citizens but to the people living all over the world.

Hollywood superstars are the real asset for their economy.

Judicial system of America

Judicial System of America US Supreme Court The US Supreme Court comprises of a chief justice and eight associate justice of America. As per the guidelines and discretion, the Supreme Court hears few cases every year that it is asked to solve.

Those cases start at state or federal courts and mostly involve vital questions regarding the federal or constitutional law.

Judicial System of America Courts of Appeal

US had 94 judicial districts that are arranged into twelve regional circuits, each circuit has its own US court of appeal.

The hearings for people from district courts situated within circuit are conducted at court of appeals.

Also the court of appeals has nationwide jurisdiction for federal circuit to hear the appeals in particular cases like those involving the patent cases and laws decided by the court of Federal Claims and the court of International Trade.

Judicial system of America District Courts

The district courts are federal court system trail's court.

As per the limits set by the constitution and the congress, the district court has jurisdiction for hearing all federal category cases, including both criminal and civil matters.

Every day several people across the country are chosen for the jury and assist decide few of such cases.

The federal judicial districts are 94 in number, one district court for each state.

The Virgin Islands, Northern Mariana Islands and Guam have their separate district courts that hear different federal cases including the bankruptcy cases.

Judicial System of America Bankruptcy Courts The bankruptcy courts solve the cases of the individuals who are not able to pay back their creditors.

They are granted a fresh start by clearing their assets to return their debts or by preparing a repayment plan.

This judicial system also helps troubled businesses and offers orderly distribution to the creditors through liquidation or reorganization.

The procedures are guided by the Title 11 in the US bankruptcy code.

The basics of bankruptcy provides basic knowledge to the creditors, debtors, media, court personnel and general public on various aspects of federal bankruptcy laws.

The bankruptcy code was amended in year 2005 to require that many individual debtors fulfill an exclusive briefing through an approved counseling agency prior to filing a case.

3. Presidential system of America

John Adams(1797-1801)

Thomas Jefferson(1801-1809)

George W H Bush(1989-1993)

Bill Clinton(1993-2002)Name at birth: William Jefferson Blythe

Date of Birth: 19 August 1946. Birthplace: Hope, Arkansas. Best Known As: 42nd President of the United States, 1993-2001.

George W Bush(2001-2009)Born July 6, 1946.Served as the 43rd President of the United States from 2001 to 2009, and the 46th Governor of Texas from 1995 to 2000.

Barrack Obama(2009-0000)Date of Birth4 August 1961, Honolulu, Hawaii, USA. Birth NameBarack Hussein Obama Jr.

NicknameBarry Bama Rock The One

Height6' 1" (1.87 m)

9-11-2001 A darkest day of American History

Attack on World Trade Centre world trade center before attack world trade center after attack

4. Economy of America

Contents:Economy of United States Of AmericaHistory of AmericaEducationUnemployment Income & WealthFinanceInflationCurrencyTaxation & Govt. InvolvementSectors:AgricultureIndustrialEnergyManufacturingMajor Imports and Exports of AmericaAmericas Economy after 9-11

Economy Of America The economy of the United States is the largest national economy in the world in both nominal value and by purchasing power parity. Its nominal gross domestic product (GDP) was estimated as $14.4 trillion in 2008, which is about three times that of the world's second largest economy, Japan.

Its GDP by PPP is almost twice that of the second largest, China.

The U.S. economy maintains a very high level of output per person (GDP per capita, $47,422 in 2008, ranked at around number thirteen in the world).

Economy Of America The United States has been one of the best-performing developed countries. The American labor market has attracted immigrants from all over the world and has one of the world's highest migration rates. Americans have the highest income per hour worked. The United States is ranked second, down from first in 2008-2009 due to the economic crisis, in the Global Competitiveness Report. The country is the world's largest and most influential financial market, home to major stock and commodities exchanges like NASDAQ, NYSE, AMEX and CME.

History Of American Economy

History Of Americas Economy The economic history of the United States has its roots in European settlements in the 16th, 17th, and 18th centuries.

The American colonies went from marginally successful colonial economies to a small, independent farming economy, which in 1776 became the United States of America.

In 230 years the United States grew to a huge, integrated, industrialized economy that makes up over a quarter of the world economy. Founder of America C.Collumbus

After the Great Depression

For many years following the Great Depression of the 1930s, when the danger of recession appeared most serious.

Great Depression (1929-1939) highlighted

1930 UnemploymentGreat Depression (1929-1939) highlighted

1960sIdeas about the best tools for stabilizing the economy changed substantially between the 1960s and the 1990s.

In the 1960s, government had great faith in fiscal policymanipulation of government revenues to influence the economy. Since spending and taxes are controlled by the president and the U.S. Congress, these elected officials played a leading role in directing the economy. A period of high inflation, high unemployment, and huge government deficits weakened confidence in fiscal policy as a tool for regulating the overall pace of economic activity. Instead, monetary policy assumed growing prominence.

1970s Since the stagflation of the 1970s, the U.S. economy has been characterized by somewhat slower growth.

The worst recession in recent decades, in terms of lost output, occurred in the 1973-75 period of oil shocks, when GDP fell by 3.1 percent, followed by the 1981-82 recession, when GDP dropped by 2.9 percent.

Since the 1970s the US has sustained trade deficits with other nations.

In the 1970s, economic woes brought on by the costs of the Vietnam conflict, major price increases, particularly for energy, created a strong fear of inflation

1990s Output fell by 1.3 percent in the 1990-91 downturn, and a tiny 0.3 percent in the 2001 recession. The 2001 downturn lasted just eight months.

These issues have raised concerns among economists and national politicians: In recent years, the primary economic concerns have centered on: high household debt ($14 trillion) including $2.5 trillion in consumer debt. high national debt ($9 trillion) high corporate debt ($9 trillion),high mortgage debt (over $10 trillion as of 2005 year-end) high unfunded Medicare liability ($30 trillion), high unfunded Social Security liability ($12 trillion).high external debt (amount owed to foreign lenders),high trade deficits and a serious deterioration in the United States net international investment position (NIIP) (-24% of GDP) In 2006, the U.S economy had its lowest saving rate since 1933.

Overall Analysis The U.S. economy maintains a relatively high GDP per capita, with the caveat that it may be elevated by borrowing and a low to moderate GDP growth rate making it attractive to immigrants worldwide.

Crisis in 2007-08

The United States entered 2008 during a housing market correction, a subprime mortgage crisis and a declining dollar value.

On December 1, 2008, the NBER declared that the United States entered a recession in December 2007, citing employment and production figures as well as the third quarter decline in GDP.

Geographical Importance The United States is rich in mineral resources and fertile farm soil, and it is fortunate to have a moderate climate.

It also has extensive coastlines on both the Atlantic and Pacific Oceans, as well as on the Gulf of Mexico.

Rivers flow from far within the continent, and the Great Lakesfive large, inland lakes along the U.S. border with Canadaprovide additional shipping access. These extensive waterways have helped shape the country's economic growth over the years and helped bind America's 50 individual states together in a single economic unit.

Investment Mass production, corporations, such as General Electric, have been instrumental in shaping the United States.

Through the stock market, American banks and investors have grown their economy by investing and withdrawing capital from profitable corporations.

Today in the era of globalization, American investors and corporations have influence all over the world.

The American government is also included among major the investors in the American economy.

Government investments have been directed towards public works of scale (such as from the Hoover Dam), military-industrial contracts, and the financial industry.

Policies of 26 June 2009. On June 26, 2009, Jeff Immelt, the CEO of General Electric, called for the United States to increase its manufacturing base employment to 20% of the workforce, commenting that the U.S. has outsourced too much in some areas and can no longer rely on the financial sector and consumer spending to drive demand.

Education

Education in the United States In 2007, Americans stood second only to Canada in the percentage of 35 to 64 year olds holding at least two-year degrees.

Top Ten Universities of U.S in 2010

Rank University 1 Harvard University 2 Princeton University 3 Yale University 4 California Institute of Technology 5 Massachusetts Institute of Technology 6 Stanford University 7 University of Pennsylvania 8 Columbia University 9 The University of Chicago 10 Duke University

Unemployment in U.S

Unemployment Unemployment rate as a percentage of the labor force in the United States according to the U.S. Bureau of Labor Statistics

In May 2009, the unemployment rate was 9.4%.A broader measure of unemployment (taking into account marginally attached workers, those employed part time for economic reasons, and discouraged workers) was 15.9%.

Female unemployment continued to be significantly lower than male unemployment (7.5% vs. 9.8%). The unemployment among African-Americans continues to be much higher than white unemployment (at 14.9% vs. 8.6%). The youth unemployment rate was 18.5% in July 2009, the highest July rate since 1948. 34.5% of young African American men are unemployed. Nearly 50% of Detroit's working-age population is unemployed.

Unemployment data 2008-09

Income and wealth

Income & Wealth According to the United States Census Bureau, the pretax median household income in 2007 was $50,233. The median ranged from $68,080 in Maryland to $36,338 in Mississippi.

In 2007, the median real annual household income rose 1.3% to $50,233, according to the Census Bureau. The real median earnings of men who worked full time, year-round climbed between 2006 and 2007, from $43,460 to $45,113. For women, the corresponding increase was from $33,437 to $35,102. The median income per household member (including all working and non-working members above the age of 14) was $26,036 in 2006.

Income & Wealth The recently released US Income Mobility Study showed economic growth resulted in rising incomes for most taxpayers over the period from 1996 to 2005. Median incomes of all taxpayers increased by 24 percent after adjusting for inflation. The real incomes of two-thirds of all taxpayers increased over this period. Income mobility of individuals was considerable in the U.S. economy during the 1996 through 2005 period with roughly half of taxpayers who began in the bottom quintile moving up to a higher income group within 10 years. In addition, the median incomes of those initially in the lower income groups increased more than the median incomes of those initially in the higher income groups

Income and wealth

According to the United States Census Bureau, the pretax median household income in 2007 was $50,233. The median ranged from $68,080 in Maryland to $36,338 in Mississippi.

In 2007, the median real annual household income rose 1.3% to $50,233, according to the Census Bureau.The real median earnings of men who worked full time, year-round climbed between 2006 and 2007, from $43,460 to $45,113. For women, the corresponding increase was from $33,437 to $35,102. The median income per household member (including all working and non-working members above the age of 14) was $26,036 in 2006

The recently released US Income Mobility Study showed economic growth resulted in rising incomes for most taxpayers over the period from 1996 to 2005. Median incomes of all taxpayers increased by 24 percent after adjusting for inflation. The real incomes of two-thirds of all taxpayers increased over this period. Income mobility of individuals was considerable in the U.S. economy during the 1996 through 2005 period with roughly half of taxpayers who began in the bottom quintile moving up to a higher income group within 10 years. In addition, the median incomes of those initially in the lower income groups increased more than the median incomes of those initially in the higher income groups. Income and wealth

Finance

Stock Market The New York Stock Exchange is a stock exchange located at 11 Wall Street in lower Manhattan, New York City, New York, USA.

It is the largest stock exchange in the world by United States dollar value of its listed companies' securities.

As of October 2008, the combined capitalization of all domestic NYSE listed companies was US$10.1 trillion.

NASDAQ NASDAQ, is an American stock exchange. It is the largest electronic screen-based equity securities trading market in the United States.

With approximately 3,800 companies and corporations, it has more trading volume per hour than any other stock exchange in the world.

Inflation in America

U.S Inflation rate

20002.73.23.83.13.23.73.73.43.53.43.43.43.420013.73.52.93.33.63.22.72.72.62.11.91.62.820021.11.11.51.61.21.11.51.81.52.02.22.41.620032.63.03.02.22.12.12.12.22.32.01.81.92.320041.91.71.72.33.13.33.02.72.53.23.53.32.720053.03.03.13.52.82.53.23.64.74.33.53.43.420064.03.63.43.54.24.34.13.82.11.32.02.53.220072.12.42.82.62.72.72.42.02.83.54.34.12.820084.34.04.03.94.25.05.65.44.93.71.10.13.820090.00.2-0.4-0.7-1.3-1.4-2.1-1.5-1.3-0.21.82.7-0.4

Currency and Central Bank

Currency and Central Bank The United States dollar is the unit of currency of the United States. The U.S. dollar is the currency most used in international transactions. Several countries use it as their official currency, and in many others it is the de facto currency.

The federal government attempts to use both monetary policy (control of the money supply through mechanisms such as changes in interest rates) and fiscal policy (taxes and spending) to maintain low inflation, high economic growth, and low unemployment. A relatively independent central bank, known as the Federal Reserve, was formed in 1913 to provide a stable currency and monetary policy. The U.S. dollar has been regarded as one of the most stable currencies in the world and many nations back their own currency with U.S. dollar reserves.

Currency and Central Bank During the last few years, the U.S. dollar has gradually depreciated in value and its reserve currency status is no longer as high as previously. With increased US debt, policy that's weakening the dollar and the EU signing the Lisbon Treaty, the dollar is less of a global currency standard.

The dollar used gold standard and/or silver standard from 1785 until 1975, when it became a fiat currency.

Taxation & Govt. Involvement

Regulations The U.S. federal government regulates private enterprise in numerous ways. Regulation falls into two general categories.

the government has sought to prevent monopolies.

Another form of economic regulation, antitrust law.

Bank regulation in the United States is highly fragmented compared to other G10 countries where most countries have only one bank regulator.

Other Regulations Occupational Safety and Health Administration.

United States Environmental Protection Agency.

Food and Drug Administration.

economic deregulation during the 1970s, 1980s, and 1990s.

The 1998 Tobacco Master Settlement Agreement

Taxation in the United States

taxationTaxation in the United States is a complex system which may involve payment to at least four different levels of government and many methods of taxation. United States taxation includes local government, possibly including one or more of municipal, township, district and county governments. The National Bureau of Economic Research has concluded that the combined federal, state, and local government average marginal tax rate for most workers to be about 40% of income.The Tax Foundation concluded that government at all levels will collect 30.8% of the nation's income for 2008

Sectors

Energy Sector of the United States The United States is the largest energy consumer in terms of total use, using 100 quadrillion BTUs (105 exajoules, or 29000 TWh) in 2005.

The U.S. ranks seventh in energy consumption per-capita after Canada and a number of small countries.

The majority of this energy is derived from fossil fuels: in 2005, it was estimated that 40% of the nation's energy came from petroleum, 23% from coal, and 23% from natural gas. Nuclear power supplied 8.4% and renewable energy supplied 6.8%, which was mainly from hydroelectric dams although other renewables are included such as geothermal and solar energy.

Oil American dependence on oil imports grew from 24% in 1970 to 65% by the end of 2004. At the current rate of unchecked import growth, the US would be 70% to 75% reliant on foreign oil by the middle of the next decade.

Transportation has the highest consumption rates, accounting for approximately 68.9% of the oil used in the United States in 2006, and 55% of oil use worldwide.

Agriculture Agriculture is a major industry in the United States and the country is a net exporter of food. The United States controls almost half of world grain exports.

Products include wheat, corn, other grains, fruits, vegetables, cotton; beef, pork, poultry, dairy products; forest products; fish.

Manufacturing USA is the leading manufacturer in the world with a 2007 industrial output of US$2,696,880 millions. Main industries are petroleum, steel, motor vehicles, aerospace, telecommunications, chemicals, electronics, food processing, consumer goods, lumber, mining. A total of 3.2 million one in six U.S. factory jobs have disappeared since the start of 2000

Imports and Exports of U.S

Exports of America

Americas Top Exports to Other Countries in 2008

Civilian aircraft US$74 billion, up 1.3% from 2007 (5.7% of total US exports). Semiconductors $50.6 billion, up 0.3% (3.9%)

Passenger cars $49.6 billion, up 13.3% (3.9%)

Medicinal, dental and pharmaceutical preparations $40.4 billion, up 15% (3.1%)

Other vehicle parts and accessories $39.9 billion, down 10.1% (3.1%)

Other industrial machinery $38.1 billion, down 0.6% (3%)

Fuel oil $34.9 billion, up 124.1% (2.7%)

Organic chemicals $33.4 billion, up 5.5% (2.6%)

Telecommunications equipment $32.9 billion, up 4.6% (2.6%)

Plastic materials $31.6 billion, up 8.7% (2.5%).

Fastest-Growing U.S. Exports to Other Countries in 2008

Fuel oil US$34.9 billion, up 124.1% from 2007 Metallurgical grade coal $5.8 billion, up 97.8% Chemical fertilizers $10.8 billion, up 71%

Other coal and fuels $2.8 billion, up 66.6%

Non-farm tractors and parts $3.4 billion, up 62.2%

Rice $2.3 billion, up 57.1% Oilseeds and food oils $3.2 billion, up 56.8% Natural gas liquids $3.3 billion, up 54.7%

Natural gas $4.9 billion, up 54.6%

Un manufactured goods from agricultural industry $3.3 billion, up 53.8%.

Fastest-Declining U.S ExportsAudio and video media ... US$584.3 million (down 67.5% from 2006, down 56.6% from 2003) Metalworking machine tools ... $6.7 billion (down 29.3%, down 27.8%) Computer accessories ... $29.4 billion (down 18.7%, down 6.1%)

Manufactured tobacco ... $1.2 billion (down 15.1%, down 38.5%)

Complete military aircraft ... $4 billion (down 10.5%, up 85%) Textile apparel and household goods ... $4.7 billion (down 9.3%, down 20.5%)

Cotton fiber cloth ... $2.9 billion (down 9%, up 2.2%)

Military apparel and footwear ... $654.3 million (down 5.6%, down 22.6%) Pulp and paper machinery ... $2.7 billion (down 5.4%, up 13.7%)

Aircraft launching gear ... $329.8 million (down 4.4%, up 92.4%)

Electric energy ... $991 million (down 4.3%, up 31.1%)

Semiconductors ... $50.2 billion (down 4.3%, up 8.8%).

Overall American Exports Analysis Generating a Gross Domestic Product (GDP) valued at US$14.265 trillion, America was the worlds richest country in 2008 based on economic output.

With a population of 307.2 million Americans who enjoyed an average GDP of $47,000 per person last year, America was also the 10th wealthiest nation in terms of GDP per capita.

Americas largest export clients were Canada (20.1%), Mexico (11.7%), China (5.5%), Japan (5.1%), Germany (4.2%) and the United Kingdom (4.1%).

America Exported $74 Billion in Civilian Aircraft

America Exported $50.6 Billion in Semiconductors

Imports of America

Americas Top Imports from Other Countries Crude oil US$341.9 billion, up 44.1% from 2007 (16.3% of total US imports)

Passenger cars $125.6 billion, down 6.2% (6%)

Medicinal, dental and pharmaceutical preparations $78.9 billion, up 10% (3.8%)

Other vehicle parts and accessories $64.9 billion, down 11.5% (3.1%) Other household goods $61.6 billion, up 9.9% (2.9%) Computer accessories $60.2 billion, down 4.5% (2.9%)

Other petroleum products $52.3 billion, up 8.2% (2.5%)

Cotton apparel and household goods $49.5 billion, down 2.7% (2.4%) Telecommunications equipment $44.8 billion, up 1.1% (2.1%)

Video equipment (television receivers, VCRs, DVD players) $41 billion, up 3% (1.9%).

Fastest-Growing U.S. Imports from Other Countries

Numismatic collectible coins US$1.3 billion, up 268.6% Sulfur and non-metallic minerals $1.8 billion, up 105.9%

Other coal and related fuels $4.7 billion, up 86.7%

Fertilizers and pesticides $15.1 billion, up 58.5%

Food oils and oilseeds $5.3 billion, up 58%

Oilfield and drilling equipment $12.5 billion, up 57%

Feedstuff and food grains $4.5 billion, up 54.4%

Other non-agricultural foods and additives $709.4 million, up 53.6%

Un manufactured steelmaking materials $10.8 billion, up 48%

Crude oil $341.9 billion, up 44.1%.

Imports of U.SUS Imports $342 Billion in Crude Oil for 2008

America Paid $125.6 Billion for Foreign Cars

US Imported $60.2 Billion in Computer

The impact on economy of America after 9-11-2001 attack