The `if`/`elif`/`else` structure is a common way to control the flow of a program, allowing you to execute specific blocks of code depending on the value of some data. If the condition following the keyword `if` evaluates as `true`, the block of code will execute:
Note that parenthesis is not used before and after the condition check as in other languages .
```python
if True:
print('If block will execute!')
```
```python
x = 5
if x > 4:
print("The condition was true!") #this statement executes
*Note that there is no condition following the `else` keyword - it catches all situations where the condition was `false`*
Multiple conditions can be checked by including one or more `elif` checks after your initial `if` statement but only one condition will execute:
```python
z = 7
if z > 8:
print("I won't print!") #this statement does not execute
elif z > 5:
print("I will!") #this statement will execute
elif z > 6:
print("I also won't print!") #this statement does not execute
else:
print("Neither will I!") #this statement does not execute
```
*Note only the first condition that evaluates as `true` will execute. Even though `z > 6` is `true`, the `if/elif/else` block terminates after the first true condition. This means that an `else` will only execute if none of the conditions were `true`.*
We can also create nested if's for decision making. Before preceding please refer to the href='https://guide.freecodecamp.org/python/code-blocks-and-indentation' target='_blank' rel='nofollow'>indentation guide once</a> before preceding.
Let's take an example of finding a number which is even and also greater than '10`
```
python
x = 34
if x % 2 == 0: # this is how you create a comment and now, checking for even.
if x > 10:
print("This number is even and is greater than 10")
else:
print("This number is even, but not greater 10")
else:
print ("The number is not even. So point checking further.")
```
This was just a simple example for nested if's. Please feel free to explore more online.
While the examples above are simple, you can create complex conditions using <ahref='https://guide.freecodecamp.org/python/comparisons'target='_blank'rel='nofollow'>boolean comparisons</a> and <ahref='https://guide.freecodecamp.org/python/boolean-operations'target='_blank'rel='nofollow'>boolean operators</a>.