Summary  
Type safety enforces that every variable in code only holds values of its declared type, with mismatches detected at compile time to prevent errors and clarify code intent.

General domain of usage  
Coffee shop application

In Java, every variable has a specific data type, and that type determines what kind of value it is allowed to store. This idea is called **type safety**.

The main purpose of type safety is simple: Java makes sure that you don't accidentally put the wrong type of data into a variable.

## How Type Safety Works

Once a variable is created with a certain type, Java expects it to always follow that rule.

For example, this is valid:
```java
int coffeesSold = 35;
```

But this causes an error — text cannot go inside an `int`:
```java
coffeesSold = "Thirty Five"; // ERROR
```

The same applies to `String` — it can only hold text:
```java
String coffeeName = "Cappuccino";
```

Trying to assign a number causes an error:
```java
coffeeName = 25; // ERROR
```

Java detects these mismatches **before the program even runs** and stops it from continuing.

This might seem strict at first, but it is actually very helpful. Type safety prevents many mistakes early and makes code easier to read — just by looking at the variable type, you already know what kind of data it should hold. As programs become larger, this becomes extremely important for avoiding confusing bugs and unexpected behavior.

What is the main purpose of type safety in Java?

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