'abc' and 'cba'

Question

Your task is simple, write a single code snippet that when executed in one language outputs only the string 'abc' and when executed in another language outputs only the string 'cba'. The program should take no input.

This is a code-golf challenge.

Answer 1

PHP & HTML, 15 bytes

<?die(abc)?>cba

PHP exits with printing abc; cba is ignored.
HTML sees the PHP code as unrecognized tag (and ignores it), then prints cba.

Answer 2

Javascript and Japt, 18 15 bytes

$Pw=P="cba";$Pw

Outputs "abc" in Japt and "cba" Javascript.

Try it online!

Answer 3

Bash / 05AB1E, 27 bytes

"printf" "abc\n" '#' r.ÁR¦¦

Try it online Bash

"printf" "abc\n" '#' r.ÁR¦¦
 │        │       └useless arguments
 │        └abc\n argument
 └printf command

Try it online! 05AB1E

"printf" "abc\n" '#' r.ÁR¦¦
 │        │       │ ││ │  └remove first two chars
 │        │       │ ││ └rotate stack 1 right
 │        │       │ │└reverse stack
 │        │       │ └push space character to stack
 │        │       └push # character to stack
 │        └push string "abc\n" to stack
 └push string "printf" to stack

---

Bash / 05AB1E, 24 bytes (without new line)

"printf" "abc" '#' r.ÁR?

Try it online Bash

"printf" "abc" '#' r.ÁR?
 │        │     └useless arguments
 │        └abc argument
 └printf command

Try it online!

"printf" "abc" '#' r.ÁR?
 │        │     │ ││ │ └print stack without newline
 │        │     │ ││ └rotate stack 1 right
 │        │     │ │└reverse stack
 │        │     │ └push space character to stack
 │        │     └push # character to stack
 │        └push string "abc\n" to stack
 └push string "printf" to stack

Answer 4

A0A0 and FiM++, 123 bytes

(
>P97
P98
P99

)
Dear Princess Celestia: A!
Today I learned B.
I said "cba"!
That's all about B!
Your faithful student, C.

The parentheses at the top open a block comment in FiM++, so the A0A0 code in it is ignored by FiM++. A0A0 starts at the second line because of the preceding > and then print "abc", halting on the empty line after it. FiM++ ignores the block comment and just executes a basic program that prints "cba". The first and last lines are for the class declaration, the second and fourth lines are for the main method, with the third line actually printing "cba".