Stephen Wilhite was born in West Chester, Ohio, on March 3, 1948. His father, Clarence Earl Wilhite, was a factory worker and his mother, Anna Lou Dorsey, was a nurse.

Later in life, Mr. Wilhite captured the history of his invention in a three-page document that he shared with his children and grandchildren, his wife said.

When one of his granddaughters, Kylie, told her computer teacher that her grandfather had invented the GIF, the teacher did not believe her, Ms. Wilhite said. This prompted Mr. Wilhite to write a letter to the teacher to confirm the story. “Then he signed it Steve Wilhite and he said, ‘Google it,’” Ms. Wilhite said.

Mr. Wilhite retired at 51 after a stroke, but he kept busy using his computer programming skills to augment his model railroad, a hobby that his wife said was supposed to be confined to the basement of his home but spilled into other rooms, with Mr. Wilhite building model-train bridges in his upstairs office.

Ms. Wilhite said that her husband also loved to spend time outdoors and that they went on many camping trips with her son Rick, who she said was one of Mr. Wilhite’s “best buddies.”

They traveled from their home in Milford, Ohio, to the tip of Florida and to the Grand Canyon, she said. “Steve loved the pine trees in the north, and I love the ocean, so that gave us a big span,” Ms. Wilhite said.

The couple married in 2010, when they were both in their 60s. Ms. Wilhite said that their first date was at a Cracker Barrel the year before they married.