A statement block consists of a sequence of zero or more executable statements, executable constructs, FORMAT statements, or DATA statements embedded in another executable construct and are treated as a single unit.
Within a program, you can not transfer control from outside of the statement block to within the statement block. You can transfer control within the statement block, or from within the statement block to outside the block. For example, you can have a GO TO statement branching to a label that is within a statement block. You can not branch from a GO TO statement outside the statement block.