What was going on when I was born?

WHAT is a room - some version of which will accompany us all of our lives? Even as we hunt it or build it we seldom halt to examine further this companion to human consciousness, omnipresent as sleep or dream. Some of us, though, are bedouins in spirit until the end. How is it that the room or rooms I live in are always my favorites, yet I never think of them as the final ones - as I would prefer them to be. I even have trouble living in two Remembered Rooms This is the first article of a series that will appear from time to time in The Home Section. houses, as I presently do. They verge toward a common denominator, like any place lived in by me and mine. Both houses and their rooms offer a place to live, work, cook, eat, laugh and muse in - and both are easy on the bones and the eye. Yet they form a kind of double personality that makes me uneasy, as if I'm lying to myself a little. I was brought up to be loyal to one place. We get our room habits from our parents, or in revolt against them. Mine, by the time I knew them, were New Yorkish in the matter of moving but conservatively so - that is, they lived in the same apartment until I was 15; then changed quarters twice before they died.

Scientists have isolated a previously unknown virus and used it to infect monkeys with a disease that closely resembles acquired immune deficiency in humans. The scientists, at the University of California at Davis, believe the finding may represent an important step in determining the cause of human AIDS. Most reseachers believe the human syndrome is a result of some undetected infectious agent, presumed to be a virus. The new research appears to be the most significant laboratory achievement made so far in support of that theory.

Representative Thomas P. O'Neill Jr., the Speaker of the House, said today that he would like to retire from Congress at the end of the year and become Ambassador to Ireland ''or some place like that.'' The 71-year-old Massachusetts Democrat acknowledged that such an eventuality depended on the election of a Democratic President, which he called ''definitely in the realm of possibility.'' Otherwise, he said in an interview, ''I'll definitely leave after the next term,'' which ends in 1986. In either case, Mr. O'Neill predicted he would be succeeded as Speaker by Representative Jim Wright of Texas, the House majority leader. This would be a political shift to the right, because Mr. O'Neill considers himself an unvarnished liberal, steeped in New Deal traditions, while Mr. Wright is a moderate who, in the Speaker's words, ''is in the center of our party.''

Prime Minister Pierre Elliott Trudeau announced today that he had decided to resign after more than 15 years as head of the Canadian Government. He said it was ''the appropriate time for someone else to assume this challenge.'' Mr. Trudeau, 64 years old, whose fondness for the dramatic gesture has been as characteristic of him as the red rose he habitually wears in his lapel, made his announcement during a paralyzing snowstorm and while Parliament was in recess. But he did not do so in any public appearance.

Robert L. Crandall, the president and chief operating officer of American Airlines, said yesterday that the airline would use its new McDonnell Douglas Super 80 aircraft to build a low-cost carrier inside the old high- cost airline that could compete with other low-cost carriers. Yesterday, American confirmed reports that it had ordered 67 of the McDonnell Douglas planes in what was believed to be one of the largest orders in airline history. Although American officials would not disclose financial details, the deal is expected to be worth more than $1.3 billion. One American official said each plane would normally sell for $22 million, but because of the size of the order, the airline had received a discount. American also said it had options to buy another 100 planes.

A divided gubernatorial commission recommended today that large amounts of inexpensive hydroelectric power be shifted from upstate to homes and businesses downstate and that some power be reserved for business to help promote jobs. The commission, formed by Governor Cuomo last July, split 5 to 4 in its final report over how to distribute the power generated by the Niagara and St. Lawrence-Franklin D. Roosevelt Power Projects. The two projects, which generate 20 billion kilowatt hours, or about 19 percent of the state's annual energy production, produce the cheapest electricity in New York State. Currently, nearly all the hydropower generated by the two projects is distributed under contracts signed more than two decades ago. When those contracts expire, beginning next year, Federal and state law will compel drastic reallocations of the hydropower across the state unless the law is changed, according to the commission.

The jetliner that ran out of runway and rolled into tidal waters at Kennedy International Airport on Tuesday was flying at an abnormally high speed when it leveled off for a landing, Government officials said yesterday. Major questions that confronted investigators were how far down the 8,400-foot runway the Scandinavian airliner, a DC-10, finally touched down and whether the plane's brakes and engine reversers were working properly. Two passengers were quoted as saying the plane seemed to float an unusually long distance before touching the pavement. According to the Government officials, the plane was apparently flying at a ground speed of 205 knots as it crossed the airport boundary and began to level off. This was apparently a great deal faster than a DC-10 would normally be traveling at that point. One DC-10 pilot said it would be unusual for such a plane to have a ground speed faster than 150 to 155 knots unless the weather was extremely bad or the plane encountered a sudden change of wind direction. A pilot cannot tell his ground speed from cockpit instruments, only his speed through the air.

A picture caption yesterday with an article about the Federal Budget misidentified the member of Congress leaving the White House with Senator Mark O. Hatfield. He was Senator Pete V. Domenici.

Because of an editing error, a dispatch yesterday from Amritsar, India, on unrest among Sikhs misstated the role of Hinduism. India has no state religion.

The United States trade deficit hit a record $9.47 billion in January, the Commerce Department reported today. One analyst called the figure an ''economic disaster'' as a flood of foreign imports and increased demand for oil darkened an already gloomy trading picture. Both Government and private economists said the January figure bolstered their fears that this year's red ink would easily top $100 billion, surpassing last year's trade deficit of $69.4 billion.

CERTAIN kinds of people, with a nose for the arcane and the knack of making even the most daunting spaces charming, always seem to stumble on unusual places to live. Remaining relics of an earlier age, carriage houses, back houses and firehouses, are seized upon by these courageous spirits, who prefer to cope with crumbling walls and unstable floorboards rather than face less interesting, spic-and-span spaces. Virginia and Edward Bauer are one example of this adventurous breed. They did not choose their Hoboken, N.J., home because Frank Sinatra's father had worked as a fireman there, although they do admit it added to the charm. Nor was the fact that the building had recently been named a historic landmark a crucial reason for their move. ''After living in a quirky old Victorian house in the suburbs we wanted something closer to New York that was equally interesting,'' Mrs. Bauer said. Interesting it certainly is. The Bauers are among the first tenants to live in the recently renovated firehouse. From the street the building looks exactly as it did when it was built in 1898: ''Engine Number 5'' is etched over a central arched doorway. Were it not for well-dressed people entering and leaving there would be no clue that this is a three-apartment building.

Pierre Elliott Trudeau plans to resign after serving as Canada's Prime Minister for more than 15 years. Iona Campagnola, president of the Liberal Party, said Mr. Trudeau would remain in office as leader of the party and head of Government until a successor is chosen in a national convention. (Page A1, Column 6.) Moscow vetoed a French proposal in the United Nations Security Council that would have sent an international peacekeeping force to Lebanon. The proposal was backed by 13 members of the 15-member Council. (A1:3.)