iMac 27" i7 2009: 32-bit mode??

[mtbdudex]

My iMac 27" i7 2009, went to sys prefs and opened it, noticed it said "32-bit", what the heck does that mean? I thought 64 bit OS?
Or, always there and I'm getting senile in my older age?

Did my iMac re-start into some "32-bit safe mode"??

 

[Hellhammer]

Finder > Applications > Right-click System Preferences > Show Info > Uncheck "Open in 32-bit mode"

 

[mtbdudex]

Finder > Applications > Right-click System Preferences > Show Info > Uncheck "Open in 32-bit mode"

thank you