What is a house system, and which one is right?
There is more than one way to divide the sky into twelve houses, and the choice moves planets between houses near the boundaries. Placidus, the common modern default, divides by time; whole-sign, the oldest method, makes each house one whole sign; equal houses take thirty degrees each from the Ascendant.
Where astrologers disagree
This is the largest live disagreement in the field, and there is no calculation that settles it. If a planet sits near a cusp, another astrologer may place it in the next house and both are following a real tradition.
Where you see this in OrbHeaven
Your own chart is calculated from your birth details, and this definition is written out again there with your numbers in it rather than in the abstract. The chart, the glossary and thirty days of dated timeline are free, and nothing here is charged per question.
About a minute. Birth time optional, and no account until after you have seen it.
The chart
What the picture is, and what the numbers on it are measuring.