AI Overview
The abbreviation "CRT" can refer to several things, but most commonly it stands for Cathode Ray Tube, a type of display technology, or Cardiac Resynchronization Therapy, a medical treatment. It can also refer to Critical Race Theory, an academic and legal framework. 
Here's a breakdown of each:
1. Cathode Ray Tube (CRT):
A CRT is a vacuum tube that uses an electron beam to display images on a phosphorescent screen. 

It is often used for people with heart failure and certain types of arrhythmias.
CRT devices can be either CRT-P (pacemaker only) or CRT-D (pacemaker with defibrillator). 
3. Critical Race Theory (CRT):
CRT is an academic and legal framework that examines how race and racism have shaped legal systems and institutions in the United States.
It argues that racism is systemic, not just the result of individual biases, and is embedded in laws and policies.
CRT has been a subject of debate and controversy, particularly in educational settings.