Can you explain what is meant by a collection in Java and how it is used?

In Java, a collection is an object that groups multiple elements into a single structure for convenient storage, access, and management. Collections allow working with data sets, such as lists, sets, or maps.

Main features of collections:

• They can store objects of different types (usually of the same type).
• They provide methods for adding, removing, searching, and iterating over elements.
• They can have various properties: ordering, element uniqueness, fast access by key, etc.

Examples of collections in Java:

• List — an ordered list of elements, allowing duplicates.
• Set — a collection of unique elements without a specific order.
• Map — a key-value mapping.

Using collections allows efficient organization of data in programs, for example:

List<String> names = new ArrayList<>();
names.add("Ivan");
names.add("Maria");

for (String name : names) {
    System.out.println(name);
}

Thus, collections are a fundamental tool for working with groups of data in Java.