This fact is from Working Length & Instrumentation in Conservative & Endodontics. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
Apex locator = most accurate method electronic
Working length = 0.5 to 1mm short of radiographic apex
Crown-down technique = most popular current
Step-back technique = older standardized
Gates-Glidden = coronal flaring
Protaper gold = improved flexibility
WaveOne = reciprocating single file.