My first coding project, and it had a data set and did something

 Back on my C64 now, looking back, how silly, but a DATA set to hold a move collection was my first start in understanding data structures.  Not my exact code, but the code was basically like this.

10 REM VHS Collection Search

20 DIM T$(5)

30 FOR I = 1 TO 5

40 READ T$(I)

50 NEXT I

60 INPUT "Enter VHS title to search: ", S$

70 FOR I = 1 TO 5

80 IF T$(I) = S$ THEN PRINT "Title found: "; T$(I)

90 NEXT I

100 END

110 DATA "Star Wars", "Back to the Future", "The Terminator", "Ghostbusters", "Indiana Jones"

Oh line numbers and goto

At every place there was a C64 I would run over and type

10 PRINT "TIM",,,,,,

20 GOTO 10

Filling the screen with my name :-)