The DISC Assessment looks at our basic way of operating. It is the HOW of our preferences helping to bring understanding to our behavioral style/how we do things. It is useful to understand this for ourselves and also those we work with. The assessment does not put you in a box to tell you who you are, rather it helps to highlight themes and go to behaviors of your typical way of operating. Depending on the combination you are, your behavior varies as you reflect on your task and social style, as well as your primary mode of operating versus how you might adapt under stress or a different situation. The DISC is a classic and long-standing tool.
I have worked with it since 1990 (I was in High School when it was first introduced!). Due to the simplicity, it is an excellent tool to understand your basic wiring and mode of operating and then build on this by taking additional assessments of unique strengths and styles.