# If...Then

**If...then** is a way of thinking that allows us to make decisions based on Logic.

It can help us make decisions in mathematics, computer science and everyday life.

Here we explore the basics of using if...then logic, as well as how to use "and", "or" and "not".

## Using If...Then

The basic structure of an if...then statement is simple:

**If**a condition is true,**then**something happens.

### Example: **If** it is raining, **then **I will take an umbrella.

In that example, the condition (it is raining) triggers the decision (take an umbrella).

There are two parts:

- The
**if**part is the condition that must be true for the statement to be true. - The
**then**part is the result that will happen if the condition is true.

## And Or Not

We can combine conditions together using **and**, **or** and **not**.

It works like this:

**If**(some combination of conditions) is true,**then**something happens.

### And

We can use **and** when both conditions have to be true for the statement to be true.

### Example: If it is raining **and** windy, then I will wear a raincoat.

If it is only raining or only windy then we don't make the decision. But if it is both rainy **and **windy we want that coat!

### Example: If I am hungry and I have enough money, then I will buy lunch.

If we aren't hungry or don't have money we won't be buying lunch!

### Or

**Or **is used when either condition (or both!) trigger the decision.

### Example: If it is raining **or **snowing, then I will take an umbrella.

In that example, either condition (it is raining **or **it is snowing) can be true for the decision to be true. A mix of rain and snow also works.

We can also have many conditions!

### Example: If it is raining **or **snowing **or **cloudy, then I will take an umbrella.

The result (take an umbrella) will happen if **any **of those conditions are true.

### Not

We can also make the decision when a condition is **not **met:

### Example: If it is **not sunny**, then I will take an umbrella.

### Numbers

Numbers are often part of the decision:

### Example: If you have 8 items or less, then you can use this checkout.

### Example: If the time is 8:00 and it is a weekday, then you should be out the door heading for the bus stop.

### Example: If you are not in the top 20%, then you must do extra study.

**If**the light is red,**then**you must stop.**If**the light is green,**then**you can go if it is safe.

## Conditional

**conditional**argument

## Conclusion

**If...then**, **and,** **or **and **not **are powerful ways to make logical decisions.

By understanding the basics of this logic you can make better decisions in your everyday life.