What is a programming idiom?

for (i=0; i<10; i++)

for ($i = 1; $i <= 10; $i++)

foreach ($arr as $value)

(1..10).each

array.each

if(c=GetValue())
 {...}

c = GetValue();
 if (c != 0)
 {....}

Iterator foo;
foo.reset();
while (foo.next())
{
    print(foo.value());
}