Else, Elif

An «else» conditional is dependent of an «if» statment, it usually executes if the «if» statement goes to 0 or is false.

#!/usr/bin/python

var1 = 100
if var1:
   print "1 - Got a true expression value"
   print var1
else:
   print "1 - Got a false expression value"
   print var1

var2 = 0
if var2:
   print "2 - Got a true expression value"
   print var2
else:
   print "2 - Got a false expression value"
   print var2

print "Good bye!"

Resulting in this:

1 - Got a true expression value
100
2 - Got a false expression value
0
Good bye!

The «elif» conditional allows you to check multiple times for a «true» statement inside your block of code and execute one as soon as one turn «true» Example:

var = 100
if var == 200:
   print "1 - Got a true expression value"
   print var
elif var == 150:
   print "2 - Got a true expression value"
   print var
elif var == 100:
   print "3 - Got a true expression value"
   print var
else:
   print "4 - Got a false expression value"
   print var

print "Good bye!"

Examples and more from: https://www.tutorialspoint.com/python/python_if_else.htm