You can use the same progression and make a song sound completely different. See: "Always Be My Baby," "All I Want For Christmas Is You," and "Touch My Body." Pop music theory is really simple.
LFN: B G#m D#m C# B in F#
Hot N' Cold: G D Am C in G
Not too different.
ET: Fm G# Fm G# in Fm
Roar: A# A# Gm Gm in A#
The only similarity they share is that they're two chord progressions.
But look:
Walking On Air:
Verse: A# A# Gm Gm
Chorus: D D D D F#m E C# D in F#m
TIHWD (very 90's Alt. Rock, which is why it sounded bizarre with its production...
https://www.youtube.com/watch?v=n6P0SitRwy8; https://www.youtube.com/watch?v=CkFH0KMO0G0):
Am G C F in Am
BTGOG:
Verse: Gm D# A#m A#m
Chorus: D# A F Gm in A#
Hummingbird:
Verse/Chorus: F G Em F in Em
Bridge: Am G C F (in F major!)
"Dark Horse"
F# C# Am# G# in A#m
"Birthday"
E C#m E (in B major! I bet she wrote a lot of it...)
Double Rainbow:
C G Am F (in C major!)
This stuff interests me. I know it's terribly boring to most.
ETA: I analyze the **** out of everything (that interests me)...it helps in my profession, haha.