Taking Wickets
When the bowling team has dismissed all but one of the batsmen the innings is said to be over. The batting team is said to be 'all out'.
For example, in most games, each side has 11 players, so 10 wickets need to be taken to bowl a side out.
There is an exception to this rule if one or more batsmen are injured and/or ill and are unable to bat. In such cases, when only one batsman remains not out and capable of batting, the innings is over.
Read more about this topic: End Of An Innings