QUESTION on plot's quality

[tiny0little]

could you explain (or point to a doc) what proof in a plot means? also if k32 plot shows more proof than k33, what does it mean?

$ chia plots check -n 30 -g 2021-05-06

Testing plot /media/HDD-8TB-004/CHIA/plot-k32-2021-05-06-05-28-81e8b16a30f6b06f626b02f4e5d3ca6026c6f67c203b507e786b58db2ca61dfc.plot k=32
Proofs 34 / 30, 1.1333

Testing plot /media/HDD-8TB-003/CHIA/plot-k33-2021-05-06-15-27-ed9a8045975b5f69f594fa04a2c171fc83a386ad185f146568b5214342470fbd.plot k=33
Proofs 28 / 30, 0.9333