The unlikely persistence of AppleScript | Macworld: AppleScript first appeared in System 7.1 in October 1993, as the first and eventually canonical Open Scripting Architecture (OSA) scripting language. The idea was that OSA would provide a low-level architecture for both inter- and intra-application scripting—in other words, a consistent, system-wide mechanism for multiple applications to communicate and exchange data with each other, and for users to automate tasks within any scriptable application. Instead of each application creating its own incompatible macro language, there’d be one universal way for Mac apps to be automated.
AppleScript was not originally intended to be the only OSA scripting language, but it was. The idea was that OSA was language-agnostic, and the plan was for there to be several of them eventually. AppleScript was the friendly language, derived from HyperCard’s HyperTalk (therein another story entirely) and intended for use by non-programmers. The theory being that a programming language that looked like prose rather than code might enable a broad swath of “non-programmers” to, well, program.