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| Forth |
 Title text: I NOTATION POLISH REVERSE ❤️ |
Explanation
Forth is a stack-oriented programming language. Like most stack-oriented programming languages, Forth's grammar incorporates Reverse Polish notation. For example, instead of an expression that adds two numbers via infix notation, such as 8 + 5, Forth would denote it as 8 5 +. Reverse Polish notation is not just limited to mathematical expressions in the language; control flow and function calls also analogously follow this notation.
This can be similar to Subject–object–verb word order, where a statement in English using Subject–verb–object order, as in "Sam ate apples", can be represented as "Sam apples ate".
The comic features a car with a bumper sticker that mentions Forth, but in a way where the message humorously reflects its grammar; a self-referential joke. The bumper sticker is a take on a common type of such with the format "I ❤️ [object]", where the object is what the driver publicly expresses personal attachment to. The heart symbol is an abbreviation of the word "love". A real-life example is the abbreviated form of the slogan "I Love New York", expressed as "I ❤️ NY". In this case, the sticker reading "I FORTH ❤️" is to be interpreted, following Forth's grammar, as "I love Forth".
Likely coincidental, the capitalization of the word "FORTH" also parallels the convention of how the language was stylized in its early years until the late 1970s. Likewise, it can be confused as an acronym, despite it not being so.
Furthermore, the English word order "Adjective-NounPhrase" becomes "NounPhrase-Adjective" in Forth. So the title text "I NOTATION POLISH REVERSE ❤️" is interpreted as "I love Reverse Polish notation".
Similarly, 1033: Formal Logic features a bumper sticker on a car, which involves personal expression. Reverse Polish notation is also the subject of 645: RPS.
Transcript
- [The right rear portion of a car is shown. On the bumper is a sticker that says:]
- I FORTH ❤️
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