### And, Or Expressions

The expression E1 and E2 returns true if the effective boolean values of E1 and E2 are both true. The expression E1 or E2 returns true if the effective boolean values of either or both of E1 and E2 are true.

     (for a truth table) 1 and 1

result:

1. xs:boolean: true

    1 and 0

result:

1. xs:boolean: false

    1 or 0

result:

1. xs:boolean: true

    0 or 1

result:

1. xs:boolean: true