Browse the combination catalogue
Every suit holding worth thinking about, with the best line's odds beside it. Narrow by how many cards the two hands hold between them, by how many times the line has to change hands, or by how often it brings the target home.
What one row is
A row is a holding and a target: these cards, this many tricks. The same cards played for a different number of tricks is a different problem with its own best line, so it is a different row — which is why a holding you recognise may appear here more than once. Holdings of five to eleven cards between the two hands are covered, and a holding earns a row only where the play is worth thinking about. If the obvious card is already the right one there is nothing to teach, and the holding is left out.
Reading the columns
Best line makes it is the share of layouts on which the best line guarantees the target. Guarantees is the important word: the defenders are assumed to see all four hands and to play best defence — the card that hurts you most, whether or not it is the card a book would play — so a line is credited only where it works against any defence at all. That makes these numbers lower than the ones you get by assuming honest opponents, and it makes them safe to bet a contract on. Fifty per cent is the plain finesse, which is the number to read the rest against.
Entries at worst is the most times the line can need to change hands, counted over every way the missing cards can lie. It is deliberately the worst case rather than what the line spends on the deal shown on its own page: a line you cannot afford on a bad day is a line you cannot play. Filtering to none is the useful thing a table of these numbers can do that a book cannot — it answers "I have no way back to dummy, so what can I still play for?"
Why the lengths are so uneven
The counts beside the card chips are worth a look before you pick one. Seven- and eight-card holdings carry the most, and carry more rows than there are holdings, because two posable targets on one holding is normal at those lengths — you can play for the extra trick or settle for the safe one, and the two want different cards. At the other end, eleven cards between the hands yields almost nothing: with only two cards missing there is rarely a decision to get wrong. Short holdings are thin for the opposite reason, having too few cards to arrange a choice at all.