1 Consecutive matches in which the same opponents face off.
Example: "Marina's been in a program with Su Yung for a few weeks."
1 A performer's storyline.
Example: "PAC and Cassidy are working an angle after Cassidy disrespected PAC during a match."
A program can simply begin as a way to fill space on the card for a few shows without ever truly developing into an angle. Some angles take place primarily through promos and vignettes and culminate in a single match, which wouldn't accurately be called a program.
The terms do get used somewhat interchangeably, but an angle always has story behind it; a program might not.
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