What are Helpers in CodeIgniter?
Why Interviewers Ask This
Interviewers use this question to quickly assess whether a candidate has the foundational knowledge required for CodeIgniter development. It reveals whether you understand the building blocks that more complex concepts rely on.
Answer
Helpers in CodeIgniter are collections of standalone PHP functions (not classes) that assist with specific tasks. They are organized by type and must be loaded before use. Load a helper: helper("url") or load multiple: helper(["url", "form", "text"]). Built-in helpers: url (URL-related functions like base_url(), redirect()), form (HTML form generation), text (text manipulation), html (link and img tags), date (date formatting), file (file-related functions), array (array utilities), security (xss_clean()), cookie. Load helpers globally in app/Config/Autoload.php under the $helpers array, or per-controller in the constructor. You can also create custom helpers in app/Helpers/.
Pro Tip
If you're unsure about a detail, say so honestly and explain your reasoning. Interviewers respect candidates who can think through uncertainty rather than bluffing.