Xcode is Apple’s integrated development environment (IDE) that you use to design apps for Apple products. It provides various tools to manage your entire development workflow from creating your app, to testing, submitting and optimizing it to the App store.

Multiple line comments can be written as forward-slash followed by an asterisk (/*) and end with an asterisk followed by a forward slash (*/).

Multiple line comments can be written as forward-slash followed by an asterisk (/*) and end with an asterisk followed by a forward slash (*/).

Control transfer statements used in Swift include −

• Break
• Continue
• Fallthrough
• Return

In Swift, the classes are not inherited from the base class and the classes that you define without specifying its superclass, automatically becomes the base-class.

It supports any kind of data and not only Synchronizes it, but also checks for equality. The Switch statement must be exhaustive, which means that you have to cover all possible values for your variable.

The question mark (?) is used during the declaration of a property. It tells the compiler that this property is optional and whether the property may hold a value or not.

To provide a default value for a variable.

The let keyword is used to declare constants, while var is used for declaring variables.

The guard statement evaluates a Boolean condition and proceeds with program execution if the evaluation is true.

GCD is the most commonly used API to manage concurrent code and execute operations asynchronously at the UNIX level of the system. GCD provides and manages queues of tasks.

A synchronous function returns only after the completion of a task that it orders.

An asynchronous function, on the other hand, returns immediately, ordering the task to be done, but not waiting for it.

MVC is a design pattern that stands for Model View Controller. This design pattern separates the data from its display, mediated by a View Controller.

Delegates are a design pattern. A delegate is just an object that another object sends messages to when certain things happen.

Core Data is an object graph manager, which also has the ability to persist object graphs to a persistent store, on a disk.

Reusability of an already allocated object.