Yellow and Blue bars in OSCAR

[lbl82]

   
What is the yellow bar that says 7h 55m and blue bar that say 1h 46m at the bottom of the daily statistics?

[Gideon]

Those colors corespond to the colors in the events chart and the numbers represent the days 'numbers"

[GuyScharf]

Bonjour's answer refers to the color of the bar showing the various indices.

The bars in the bottom left corner of the page represent sessions -- blocks of time you were using the CPAP machine.  The time in the bar is the length of each session.  The bar representing the first session is yellow; the bar for the second session is blue.  A third session would be yellow again.  The bars alternate between yellow and blue just to distinguish them; the color has no significance other than to be visually distinctive.  

If you disable a session by clicking on the checkbox before the session, the bar that represents that session becomes white.

[OpalRose]

And just to add to the confusion    

At the top where it says Start, End and Hours... the Hours is the sum of the two sessions.