CHICAGO. A CITY OF SUPERLATIVES

Incorporated in August 1833, as a small village where the Chicago River meets Lake Michigan, Chicago is, perhaps above all, a determined survivor. It has weathered major blows - from the Great Fire of 1871, which leveled most of its public buildings, to the sharp decline of its stockyards and railroads - which might have felled a city of any less muscle and grit.

''Stormy, husky, brawling,'' was poet Carl Sandburg's capsule description of Chicago. ''Come and show me another city,'' he wrote, ''with lifted head so proud to be alive and coarse and strong and cunning.''

Often billed as the most American of US big cities, this competitive two-newspaper town in the last few decades has spawned more than 100 lively and effective neighborhood groups (many trained in the Saul Alinsky activist tradition), a skyline of towering glass and steel high-rises, and a glamorous stretch of elegant shops along Michigan Avenue's Magnificent Mile.

The Windy City is home to nimble columnist Mike Royko (who recently jumped from the Sun-Times to the Chicago Tribune), black presidential candidate Jesse Jackson, and Nobel Prize winner Saul Bellow. And Mr. Bellow happens to be only one of 53 present or former University of Chicago faculty members and students to receive the Stockholm honor.

In part because it is sensitive to comparisons with Manhattan - many statistics tend to reaffirm its Second City status - Chicago tends to stress its own set of superlatives. It lays claim to the world's tallest building (Sears Tower), largest hotel (Conrad Hilton), tallest bank (First National), busiest airport (O'Hare), and largest department store (Marshall Field's).

Occupying one square block in Chicago's Loop, Field's last year offered ''When you leave Chicago you ain't goin' nowhere'' T-shirts in its ground-floor Chicago shop. This year they have been replaced by others insisting ''Somebody in Chicago loves me'' and ''Chicago . . . My kind of town'' baby bibs.

But for all the changes over the years, Chicago's image in the eyes of many outsiders, particular foreign visitors, remains much the same. It is seen as the city of gangsters and of corrupt and sometimes brutal machine politics. It is viewed as a city of heavy snows and heavy manufacturing which has been outpaced by foreign competition. Many see it as brash and raw-edged, lacking refinement and with an outlook more provincial than cosmopolitan.

But Chicago's population has become more and more of an ethnic mix in recent years, and the attitude toward America's global role has changed.

''Chicago was very much the center of isolationist sentiment between the 1920 s and 1940s . . . but that image that lingers on in the eyes of many just isn't true anymore,'' says John E. Reilly, president of the Chicago Council on Foreign Relations. That organization, which brings top speakers on global topics to the city on an almost daily basis, was formed in 1922 as a direct result of concern over growing isolationism.

In the 1930s, Mr. Reilly says, there was such an active adversarial relationship between the internationalist council and the more conservative Chicago Tribune (published by Col. Robert McCormick who was active in the ''America First'' movement) that no hostess who wanted peace in her home would sit representatives from both organizations next to each other at a dinner.

World War II persuaded many Chicagoans, just as numerous other Americans, Mr. Reilly says, that the United States does have a vital role to play in world affairs. He calls Tribune international coverage the best of any Chicago paper.

''Chicago now has the second-highest concentration of multinational firms in the country,'' he stresses. ''It has become a very international city.''

As for the white stuff of winter, Chicago deserves its reputation - some years anyway - as snow city. No one here will ever forget the 33-hour snowfall the city experienced in 1979. Then Mayor Michael Bilandic's failure to get it plowed is regarded as a key factor in Mayor Jane Byrne's victory the following spring.

And, for a mix of reasons, Chicago's longtime reputation as a tough crime and gangster city persists.

''When Chicago makes the news in Britain, it's largely for reasons it wouldn't be terribly proud of - and it tends to create a sort of image,'' notes Gordon Jewkes, British consul-general in Chicago.

He recalls, for instance, that the assassination attempt on Mayor Harold Washington, the double shooting in court last fall of a judge and lawyer by a Chicagoan unhappy with the way his divorce case was progressing, and several gangland shootings, were all dutifully reported on British TV and in the press over the last year.

''That image is very hard to shake,'' says Jeanette Callaway, associate director of the Chicago Crime Commission, the oldest citizens' crime group in the country and one which has kept a tally - running well over 1,000 - of all gangland slayings in the city since 1919. ''It's pretty gruesome and most say 'unknown' after 'killed by whom.' And on top of it all the image is perpetuated in the movies and newspapers. There are stories every February about the St. Valentine's Day massacre.'' And Ms. Callaway recalls that when she lived in Amsterdam a decade ago and said she was from Chicago, almost everyone said, ''Oh - Al Capone - gangsters - terrible place.''

Still, Mr. Jewkes recalls a sharp change for the better just in the last decade here in the strict ''law and order'' mentality often associated with Chicago police and politics.

''I arrived in the midst of the infamous Chicago 7 trial which was kind of an adjunct of the Vietnam war protests. The bad taste of the 1968 Democratic convention still lingered on. The city, for all its apparent self-confidence, was very troubled - living up to its worst reputation in the sense of law and order and a brutal, noncaring police force.'' When Mr. Jewkes returned to Chicago in 1982 for a second diplomatic stint, he found the atmosphere changed and the city ''a rather more pleasant place to be.''

Culturally Chicago has long been a far more exciting city than many outsiders have given it credit for.

The Chicago Symphony Orchestra is widely rated one of the world's best. And Chicagoans have traditionally given more generously to its annual fund-raising radio marathon than home supporters of any other US orchestra.

Chicago is also extraordinarily rich in museums. Several were launched during the Century of Progress fair here in 1933 and recently celebrated their 50th birthdays. There is even a Museum of Lithuanian Culture which, in addition to its educational mission, helps boost national pride for the 120,000 here of Lithuanian heritage.

And over the years this city, justifiably famous for its Lyric Opera and Goodman and Second City theater troupes, has evolved a string of some of the finest small theaters west of Broadway. But some Chicagoans would argue thatthe best show now in town is free - Chicago's weekly City Council meetings.

Certainly this city's toughest problems these days are economic. The city's tax base has been hit hard by the loss of more than 360,000 of its residents and one-fourth of its factory jobs during the 1970s. Service jobs have been growing but at a far slower, less impressive rate. Chicago's bond rating from Standard & Poor recently fell one notch to a triple B-plus. The city's population of more than 3 million is now 40 percent black and 14 percent Hispanic and has become significantly poorer. One in five Chicagoans now lives below the poverty line.

Even the city's most determined boosters concede that Chicago faces an uphill fight in improving its job, business, and tax base at this point. They take some comfort from the many Fortune (magazine) 500 companies still headquartered here (from United Airlines to Sears, Roebuck), and Chicago's special strength as an international finance center and a leader in futures and commodities. And Chicago still leads in some manufacturing fields. A mammoth new stainless steel sculpture, a gift from the Tool and Die Institute and bearing a plaque calling Chicago ''the precision metal working capital of the world,'' was unveiled on Marshall Field's southwestern corner in November.

There are also myriad new construction projects dotting the city's skyline these days - from the recently opened Neiman Marcus near Water Tower Place to architect Helmut Jahn's new curved glass Illinois government building across from City Hall.

City business leaders hope that a concerted effort by Mayor Harold Washington and Robert Meir (the University of Illinois economist who is nowdirector of Economic Development), combined with civic help and Chicago's ''I will'' determination can make a difference.

''I do think Chicago has an exceptionally committed senior business community which reports for duty and puts in time on the city's fundamental needs,'' says Kenneth Henderson, executive director of Chicago United, an interracial civic-minded business group.

Mayor Washington, who campaigned on a vow to reform machine politics and patronage in this city and claims to have made large inroads already, takes the view that more services and economic development in Chicago's neighborhoods can do much to stem the business outflow. ''Eighty percent of the jobs come from neighborhoods, but businesses are leaving so something has to be done,'' he says.''We're not anti-downtown, but we really want to plan to develop this city on a (more) parsed out, balanced out basis.''

Still, it may be Chicago's many visitors, frequently surprised and charmed by the shoreline and skyline beauty, who are in the best position to see this city's potential for growth. Andrew Neil, a Scottish-born writer for Britain's ''The Economist,'' spent several weeks in the city and in 1980 published his findings.

His conclusion: Chicago, preoccupied with its own internal battles, is the most undersold city in the United States.