What was going on when I was born?

Egyptian leaders moved quickly today to seek an orderly transition a nd to stress continuity a day after the assassination of President Anwar el-Sadat. Parliament, which is controlled by Mr. Sadat's National Democratic Party, tonight named Vice President Hosni Mubarak, Mr. Sadat's closest associate for the last six years, to succeed the slain leader as President. The nomination is subject to popular approval in a referendum in which Mr. Mubarak will be the only candidate. Although under the Constitution the referendum may be held anytime within 60 days after a presidential vacancy occurs, officials said the vote would take place on Tuesday. Effort to Stress Continuity Sufi Abu Taleb, the Speaker of Parliament, who will be Acting President until Mr. Mubarak is sworn in after the referendum, tonight appointed Mr. Mubarak Prime Minister. The appointment was seen as part of the effort to emphasize continuity and to guarantee a trouble-free transition of power. President Sadat was also Prime Minister.

The Senate approved today, by a vote of 90 to 4, a telephone deregulation bill that would free the American Telephone and Telegraph Company to expand into new data -processing and information services. For the past five years, there have been efforts in Congress to overhaul the regulations governing the telephone industry, which is dominated by A.T.& T. The bill that cleared the Senate would be the first major revision of the Communications Act since it was adopted in 1934. ''By freeing the industry from unnecessary and stifling Government controls, this bill will greatly enhance competition within the telecommunications field,'' said Senator Bob Packwood, the bill's sponsor. Senator Packwood, an Oregon Republican, is chairman of the Commerce Committee.

For millions of women around the world, the name Revlon is synonymous with the beauty business. But the company, which the late Charles Revson founded in 1932 as a nail polish business and built into the largest manufacturer of retail cosmetics in the United States, is now deeply involved in such unglamorous products as plasma derivatives, diagnostic reagents, Tums antacid tablets and lens-grinding equipment. That is not to say that Revlon has stopped pushing nail polish - or its vast range of lipsticks, eye shadows and fragrances. ''For your soul: each and every one,'' is the urgent advertising message of the House of Revlon's newest cosmetics line, Gypsy Gold, introduced last month.

Gun collectors, dealers, manufacturers and onlookers gathered yesterday afternoon at Christie's, Park Avenue and 59th Street, to bid at and watch what the auction house described as the first major auction of rifles, revolvers, shotguns and pistols in this country. The standing-room-only audience was subdued throughout, even when some of the bidding became spirited with the sale for $95,000 of a 60-year-old gold-inlaid Parker shotgun to William Jaqua, a gun dealer from Findlay, Ohio. It was a record for an American gun sold at auction and the highest price paid in the sale of 114 weapons, which also included revolvers and rifles owned by Chuck Connors, the star of the television series ''The Rifleman.'' The Winchester carbine he used in the series, which is now off the air, brought $7,500.

IT was christened Christmas in July for investors - and the Reagan tax act does bestow a host of benefits on the millions of Americans whose biggest investment is their house. Not only will the new law allow older homeowners to keep more of their profits when they sell the family home, but it will also give young people who sell their homes and reinvest the proceeds in another more time to defer paying taxes on the gain. Furthermore, the bill grants generous tax credits to investors who rehabilitate business properties, especially buildings that are certified historic structures. But the law is studded with complexities that bewilder many taxpayers. So, to help clarify the new tax act, here are some answers to commonly asked questions: Q. With all the changes in the estate law, does it still make sense to own a house jointly?

United States concern about the personal safety of President Anwar el-Sadat goes back to the Nixon Administration. According to American officials, past and present, Mr. Sadat asked President Richard M. Nixon for help and was provided with advice from the Secret Service on procedures for protecting leaders and with communications equipment from the Central Intelligence Agency that would enable him to keep his whereabouts secret. The assistance was part of an American policy of helping friendly leaders in the Middle East protect themselves against potential attacks by Libyans, Palestinian guerrillas, Moslem fundamentalists or their own armed forces. For over two decades in the Middle East, it has been difficult to separate the exigencies of personal safety from the requirements of diplomacy. For Arab leaders to deal with the United States and Israel was to court personal danger.

AT the time, most people probably didn't appreciate the farsighted import of Sid Caesar's remark, when the comedian - in the role of an astrophysicist on the 1950's ''Show of Shows'' -was asked what was the greatest problem in space; he replied, ''Closet space.'' Mr. Caesar's assessment is especially apropos the increasing number of people who find themselves living in tiny spaces where there's not enough room for books and records, for sweaters or socks, and no place to put papers but on the windowsill. Small rooms are not a new design problem. Home furnishing publications have always been packed with space-saving hints, and many decorators have made their businesses out of dealing with the impossible, the unlivable, the inflexible, which usually translates to mean a tiny room. The old solutions - the Murphy bed, the racks of wire shelving, the mirrored wall - may no longer be enough to solve today's more drastic space crunch.

Some Italian fashion houses are having difficulty maintaining the high level of excitement established at the fall and winter openings six months ago. But not Fendi and Missoni, the twin pillars of the Italian industry. Both are family enterprises, with the younger members applying new energy and a fresh outlook. At St. Andrew's Restaurant at the Milan Fair, where everyone eats in the civilized two-hour break between shows, 22-year-old Angela Missoni was sitting at her parents' table in a short white cotton culotte dress she picked up a t Vivienne Westwood's World's End Shop in London last week. Over it she wore a striped Missoni sw eater.

In the first open rift between the White House and Republican Congressional leaders over the budget, three Republican Senate chairmen have begun major revisions in President Reagan's proposal for $13 billion in new cuts. ''There's great consternation that the President's mix won't work,'' said one of the three, Pete V. Domenici, Republican of New Mexico, chairman of the Budget Committee. ''There's an evolving consensus that we need big cuts, but made up differently than the President has proposed.'' ''The most dramatic turnaround is a consensus that we need to raise some more revenues,'' the Senator said, ''but it can't all come from the revenue side.''

Commonwealth journalists urge Trudeau to shun a press law A2 Polish union convention adopts economic program A3 I.R.A. prisoners in Belfast assail new rules announced by Britain A4 Zimbabwe struggles to reduce a swollen army A5 Salvadoran opposition leader urges international mediation A7 Exile bids Egypt end Israeli ties A10 Three former Presidents in dele- gation to Sadat's funeral A11 Soviet sends chilly condolenceson Sadat's death A12 Sadat's death said to isolate the Sudan A12 Attack on executions creates up- roar in Iran's Parliament A14 Government/Politics Aide criticizes plan to ease job rights fight A19 G.O.P. try to revive campaign of Virginia Governor candidate A25 Westport lawyer nominated as U.S. Attorney for Connecticut B4 House vote holds milk price sup- ports to level Reagan wants B8 Congress approves pay raises for the military B8 Supreme Court urged to uphold campaign contributions limits B9 Obituaries Luigi Petroselli, Communist Mayor of Rome B10 Dr. Dexter M. Bullard, pioneer in psychoanalysis B10 YOM KIPPUR Because of Yom Kippur, the Jewish Day of Atonement, public schools in New York City and in many suburbs are closed today. Alternate-side park- ing is suspended in the city. All other parking rules are in effect. Home Section Home Five ingenious solutions for cop- ing with tiny spaces C1 Family Finance: Homeowners' tax questions C1 Fendi and Missoni shine in Milan C1 Hers C2 Helpful Hardware C2 Home Beat C3 Children's exhibits stress partici- pation C3 Home Improvement C4 Problems of aging: A course for offspring C5 Design Bookshelf C6 Calendar of Events C7 Gardening C9 Washington Talk Briefing A22 Required reading A22 Working Profile of Transporta- tion Secretary Drew Lewis A22 Liberal fund-raiser finds the money is pouring in A22 General Around the Nation A18 Frequent television viewers said to be complacent about health A18 Vacant Brooklyn shops getting a new lease on life B3 New York's women bus drivers win merit promotion right B3 Abbott indicted for murder in knifing of waiter B5 Health/Science Lung disability payments cut for regular smoker A18 Arts/Entertainment Malle's ''My Dinner With Andre'' at the film festival C13 Memoir recalls New York art scene in the 40's C13 Film ''Vernon, Florida,'' looks fondly at its eccentrics C14 Books about Elizabeth Taylor, Fisher and Burton reviewed C17 Grant to aid orchestras in com- missioning new works C23 Heinrich von Kleist's ''The Broken Pitcher'' is staged C27 CBS to drop gavel-to-gavel cover- age of political conventions C28 Sports Yankees beat Brewers, 5-3, in playoff opener B11 Expos beat Phillies, 3-1, in first playoff game in Canada B11 Astros beat Dodgers, 1-0, in 11th, lead series by 2-0 B11 A's defeat Royals, 2-1, lead by 2-0 B11 Islanders start season with 4-1 victory in Los Angeles B11 Dave Anderson on another test for Dave Winfield B14 News Analysis Thomas L. Friedman on role of Islamic fundamentalists A12 Editorials/Letters/Op-Ed Editorials A26 Without Sadat The view from Yovimpa Point Where to put building subsidies Letters A26 Anthony Lewis: a star falls in Egypt A27 William Safire: the perception pitch A27 Herbert Scoville Jr.: first-strike danger A27 Jeremiah Novak: China, Tai- wan's suitor A27

A state labor board yesterday suspended for 18 months the right of three New York City transit unions to the automatic deduction of dues from salary checks. It cited the heavy costs and the hazards to the public of the illegal 11-day transit strike last year, The penalty - administered by the New York Public Employment Relations Board, which governs the labor relations of public employees - will be a serious blow to the unions if it is not delayed by a court challenge. Stephen Hans, a union lawyer, called the penalty ''horrible'' and said that it could have a devastating impact on the unions. He indicated that the unions would probably challenge the ruling in court and attempt to delay its implementation during the litigation.

With the new model year barely under way, the Ford Motor Company said today that it would offer rebates of $400 to $700 to increase sales of its small cars. The Ford rebate tended to mute the effect of its recently announced 4.8 percent average increase in the prices of its 1982 models, although some of the models to which the rebates apply had not been increased in price. Ford reported a 24.1 percent increase in auto sales in September over 1980. Ford's action, following purchase incentives offered by Chrysler and General Motors, was seen by analysts as yet another indication that sales of the just-introduced 1982 models are soft.