This is the conventional use of the if in perl. Notice that there is no need for curly braces ({ and }). The body of the if ends with the appropriate keyword, end, else or elsif. The then word is generally optional, though you need it if you want to put start the body on the same line as the if, the way the last statement does.
As in most languages (excluding Python), indenting is not required, and is ignored by the interpreter. Of course, it is wise to indent in a way which reflects the structure of the code.
# Pick a random number.
rno = rand(100) + 1
print "Your magic number is ", rno, "\n"
# Perform all sort of totally uselss test on it and report the results.
if rno % 2 == 1 then
print "Ooooh, that's an odd number.\n"
else
print "That's an even number.\n"
if rno > 2 then
print "It's not prime, BTW.\n"
end
end
if rno > 50
print "That's more than half as big as it could be!\n"
elsif rno == 42
print "That's the ultimate magic number!!!!\n"
elsif rno < 10
print "That's pretty small, actually.\n"
else
print "What a boring number.\n"
end
if rno == 100 then print "Oops, you've maxxed out!\n" end



