What was going on when I was born?

Two months after the killing of Prime Minister Maurice Bishop and the United States-led invasion that followed, Grenada is a nation without a firm leader. Many Grenadians, still shaken by the upheavals, say that, for now, they do not want one. Confident of the security provided by the continuing American military presence, most Grenadians say they do not want to think about politics for the time being, and many do not seem to know, or for the moment to care very much, who is running their country. ''No, I don't really know,'' said Roland Kester, a night watchman, when asked who is in charge of Grenada. ''I can't answer that, and I wouldn't venture to.''

Colder than most, whiter than some, Christmas was a day of blinding sunshine and searing wind as bundled and huddled New Yorkers made their way to the warmth of familiar hearthsides or to rooms full of homeless strangers. New York was scarcely alone in suffering through what was one of the coldest days of the year. In many spots from the Northwest to the Southeast, record low temperatures were posted. Untouched by the freezing weather, however, a bit of the city's heart went out yesterday to the homeless, the hungry and the poor, who were invited all over town to come in from the unforgiving streets and to pile paper plates high with food. ''It's a Christmas dinner - hooray for Christmas,'' said Earl Propst, beaming infectiously as he polished off one of the hundreds and hundreds of meals of turkey served at the Sheraton Centre Hotel in mid-Manhattan.

Since 1960, when Tom Landry became coach, the Dallas Cowboys have been a model of success in the National Football League. In that span, they have won two Super Bowl titles and five Super Bowl berths. They have qualified for the playoffs the last 9 years and 17 times in the last 18 years. But as they set out on their latest playoff venture, many people question whether these Cowboys are as awesome as those of old. With a 12-4 record, they seem good enough to beat the Los Angeles Rams (9-7) in the National Conference wild-card game today at Irving, Tex. But after that, can they survive?

The companies that make aircraft for business use and individuals are finishing their worst year since 1952. But the industry is spending hundreds of millions of dollars developing new planes in the hope that the market is beginning to recover. Most major companies are designing or have already introduced high- performance planes that they hope will capture new sales to corporate buyers. In the next two years, an entirely new generation of aircraft will be introduced, from large trans-Atlantic corporate jets to small single-engine turboprop airplanes that will be 40 percent to 50 percent more fuel efficient and will fly faster and higher than most of the planes now in service.

Lebanon's Army said it defeated attacks by Shiite and Druse militiamen that broke out in Beirut over the weekend. The fighting took place near bunkers occupied by United States Marines and put the marines on battle alert. There were no reports of them participating in the fighting, though 50 rounds of smalls-arms fire were reportedly directed against them. (Page A1, Column 6.) The Rev. Jesse Jackson said the Syrian Government had invited him and a group of American clergymen to Syria to ''discuss Middle East issues and the specific question of your concern,'' the release of a captured American flier. Mr. Jackson, a Democratic Presidential candidate, sent a telegram last week to the Syrian Government asking for the release of a Navy flier, Lieut. Robert Goodman, who was shot down Dec. 4 in a bombing raid on Syrian positions in Lebanon. (A13:1.)

Orders for machine tools in November dropped 21 percent from October, but were nonethless more than double the level of orders in November 1982, according to a trade association report released yesterday. Analysts said the month-to-month drop reported by the National Machine Tool Builders' Association was insignificant and that the 114 percent increase from the previous November indicated that the still-depressed industry is continuing its slow recovery. Referring to the month-to-month decline, Joe T. Franklin Jr., the association's statistical director, said, ''I don't think the drop in November in any way represents a change in the upward trend. With orders as low as they are, a drop of a few million dollars from one month to the next has no real significance.''

Imagine the farm of the future. Such an operation might fight insects less by bombing them with huge doses of chemicals than by blending sex attractants into insecticides to halve pesticide use. This farm of the future would have many crops that would be sown, cultivated, fertilized, harvested, packed and shipped untouched by human hands. Photoelectric cells would spot which fruit was ready to pack so that only ripe fruit reached the market. Underground moisture sensors implanted over dozens of square miles would relay data to a master computer, which would electronically bark orders to irrigation pumps providing water to cropland.

Consumers in the Western United States have been paying substantially higher interest rates on loans than individuals elsewhere in the country, according to two recent surveys. A study conducted by the Dun & Bradstreet Corporation of 200 banks across the United States showed that Western banks charged more than the national average on most types of consumer loans - mortgages, automobile loans, loans to purchase durable goods and unsecured personal loans. In an earlier study that showed similar results, the Bank Rate Monitor of Miami Beach last September conducted a survey of interest rates charged on unsecured personal loans by the nation's 25 largest banks. The highest rates by far were those charged by banks on the West Coast.

''It is almost a rare thing to die a natural death in this country.

The Lebanese Army reported successes today after fierce overnight battles with Shiite and Druse militiamen that followed a French pullout from positions in the southern suburbs. During the fighting, close to bunkers occupied by the United States Marine contingent in Beirut's four-nation force, about 50 rounds of small-arms fire were directed against American positions, a Marine spokesman said, but there were no casualties. The fighting, in which at least 13 people were reported killed, was the most serious combat since a cease-fire was declared Dec. 16. The battle started Saturday night after French troops pulled back from exposed positions near the Shatila and Sabra Palestinian refugee camps in the southern suburbs - the scenes of massacres by Lebanese Christian Phalangist gunmen in September 1982.

As cable television companies spend millions of dollars to install new, high- technology systems around the country, the industry is plagued by a growing problem that even state-of-the-art gadgetry may not cure: poor service to consumers. Subscriber complaints range from the inability to reach their cable companies by telephone, to incorrect billing, to systems where television images flicker, turn into inscrutable squiggles or dissolve into snow. The problems have troubled new, sophisticated cable systems in large cities like New York, Dallas and Cincinnati as well as small, older systems from Wyoming to South Carolina. There are many reasons for poor reception and other consumer problems. For one, cable technology is far more complex than the technology used in broadcast television, so more things can go wrong. In addition, the cable industry is engaged in a rapid building program that, critics say, has left little time to develop customer services in new systems and has drained funds from the maintenance of the older ones.

Castor Fernandez, the president of Castor Spanish International, one of the nation's largest Hispanic advertising agencies, has a copy of John Naisbitt's book ''Megatrends'' on a small coffee table in his office. He keeps it handy as evidence of an important trend in marketing and advertising. ''Naisbitt says that by 2000 there will be three languages: English, Spanish and computer,'' said Mr. Fernandez, who came to the United States from Cuba in 1961. ''The need to reach the growing Spanish-speaking population will result in all Americans learning Spanish.''