Welcome! Today's subject is Encapsulation, a cornerstone of Object-Oriented Programming (OOP). Encapsulation bundles data and the operations that we perform on them into one unit, namely an object. It guards data against unwanted alterations, ensuring the creation of robust and maintainable software.

In TypeScript, encapsulation is enhanced with type annotations, providing additional checks at compile-time to ensure error-free operation. Prepare yourself for an exciting journey as we delve into how encapsulation works in TypeScript and explore the vital role it plays in crafting predictable and type-safe software.

Starting with the basics, encapsulation is the practice of packaging data and the methods that modify this data into a single compartment known as a class. It safeguards the data in an object from external interference.

To illustrate, consider a TypeScript class representing a bank account. Without encapsulation, the account balance could be directly altered. With encapsulation, the balance can only change through specified methods, like depositing or withdrawing. TypeScript enhances this with type annotations for class properties and method parameters.

Encapsulation restricts direct access to an object's data and prevents unwanted data alteration. This principle is comparable to window blinds, allowing you to look out while preventing others from peeping in.