Soft vs Hard Hand
A blackjack distinction based on the ace: a 'soft' hand counts an ace as 11 and cannot bust on the next card, while a 'hard' hand has no such flexible ace.
Definition
In blackjack an ace can count as 1 or 11. A 'soft' hand is one where an ace is currently counted as 11, so the total can absorb a large card without busting (for example, Ace-6 is a 'soft 17'). A 'hard' hand either contains no ace or must count every ace as 1 to avoid busting (for example, 10-7 is a 'hard 17', and Ace-6-10 becomes a hard 17 because the ace can no longer be 11). The distinction changes correct play significantly: soft hands are often hit or doubled aggressively because there is no immediate bust risk, whereas the same numeric total as a hard hand may call for standing. Dealer rules are frequently defined by this too, such as 'dealer hits on soft 17'.
Worked example
You hold Ace-6, a soft 17. Because the ace can still count as 1, you cannot bust by taking a card, so basic strategy often says hit or double rather than stand. Compare 10-7, a hard 17: taking another card risks busting, so you stand.
Why it matters
For learners, the soft/hard concept explains why two hands with the same number are played differently, a common early stumbling block. For professionals, the 'hits/stands on soft 17' rule is a headline detail that measurably shifts the house edge.