Quick answer
A Pairs hand is made of pairs and singles only, which means no joker can be used anywhere in it, and it is usually among the highest paying on the card.
How to recognise it in a deal
Several natural pairs already in the deal are the only honest reason to try one. Without them every missing tile must be drawn or called naturally, so a Pairs hand attempted on hope is the commonest way to end up with a dead rack.
Pairs Hands in the glossary, or have your own deal read free to see which direction it favours.
5 dealt hands that went this way
Each one is a real deal, read tile by tile. Reading several in a row is how the shape stops being a card section and starts being something you recognize on your rack.
September 12 (5 pairs (jokers can't fill pairs), strong, stay the course)
July 12 (4 pairs (jokers can't fill pairs), promising, needs shaping)
July 9 (4 pairs (jokers can't fill pairs), promising, needs shaping)
July 6 (4 pairs (jokers can't fill pairs), promising, needs shaping)
June 19 (3 pairs (jokers can't fill pairs), promising, needs shaping)
Other categories
Want this read done on your own tiles? The coach does exactly this, free: get your hand read. A fresh hand goes up every morning on the daily page.