Lightroom Catalog

[Keshav360]

I'm just new to this "Ligtroom" world and went through many articles to understand how catalog works . But I still remain confussed : is 'Preview' same as a JPEG or a photo  in a lower resolutionIs ? and does Lightroom creates a new preview or a new image for every new adjustment I make or it just keeps a preview and refers to a database which stores all the information about all the adjustments I made ? 

[Rob_Cullen]

Before anyone can give a definitive answer you need to report the exact Version Number of your 'Lightroom'

From the Menu- Help > System Info  Copy and post the first 10 lines of the report.