Got it, thanks Miruna.

A few notes to elaborate on this, since this is a common point of confusion:

The client applications support automated client-side text extraction (i.e. pulling existing text from electronic documents such as Office or PDF docs and putting that text into what Laserfiche calls "text pages"), which allows for certain actions such as using pattern matching to capture certain information within the text. 

However, if your use case is simply searchability, it's worth noting that the text from documents that have an iFilter (which includes Office docs and some but not all PDFs) is automatically placed into search indexing through server-side processing even if text pages aren't created.