What are the differences between using data streams and regular loops in programming?

Differences between using data streams (Streams) and traditional loops in programming:

• Imperative vs declarative style: Loops are an imperative approach, where the iteration process is explicitly described. Data streams are declarative, describing what needs to be obtained.
• Readability and conciseness: Streams allow writing more compact and expressive code.
• Parallelism capability: Streams can easily switch to parallel mode (parallelStream()), simplifying parallel processing.
• Lazy execution: Operations in streams are performed lazily, only when necessary.
• Functional operations: Streams support filtering, mapping, sorting, and other operations as a chain of calls.

Example in Java:

// Traditional loop
List<String> names = Arrays.asList("Anna", "Bob", "Carol");
List<String> filtered = new ArrayList<>();
for (String name : names) {
    if (name.startsWith("A")) {
        filtered.add(name.toUpperCase());
    }
}

// Using streams
List<String> filteredStream = names.stream()
    .filter(name -> name.startsWith("A"))
    .map(String::toUpperCase)
    .collect(Collectors.toList());