Most resumes you submit are routed into a resume database. Along the way, the content of the resume is converted into text for searching and indexing. Typically the resume database is an Applicant Tracking System (ATS) which can be tailored by recruiters to notify them when resumes arrive that match keywords. Because of the volume of applicants, recruiters rely on the notifications to decide which candidate resumes to read. Therefore you need to get through this gauntlet to get read by a human.