The Quantified Self is a movement to incorporate technology into data acquisition on aspects of a person's daily life in terms of inputs (e.g. food consumed, quality of surrounding air), states (e.g. mood, arousal, blood oxygen levels), and performance (mental and physical). Such self-monitoring and self-sensing, which combines wearable sensors (EEG, ECG, video, etc.) and wearable computing, is also known as lifelogging. Other names for using self-tracking data to improve daily functioning are "self-tracking", "auto-analytics", "body hacking", "self-quantifying", "self-surveillance", and "Personal Informatics". In short, quantified self is self-knowledge through self-tracking with technology. Quantified self-advancement have allowed individuals to quantify biometrics that they never knew existed, as well as make data collection cheaper and more convenient. One can track insulin and cortisol levels, sequence DNA, and see what microbial cells inhabit one's body.