Change in mathematical calculations is referred to as a delta. This can refer to a difference between two values, such as two points on a line, in particular circumstances. In other instances, like when discussing a derivative, it alludes to the rate of change.
Delta is a Greek letter that can also be employed as a variable in equations, despite the fact that it typically relates to change. Usually, if it is used to denote change, another variable, like?X, comes after it.
Uppercase and lowercase letters are used to write deltas. Lowercase deltas resemble a stylised d (?) whereas uppercase deltas resemble triangles (?). The lower-case delta is more frequently used when expressing differential equations utilising the syntax of deltas.