Not all note follow the convention in here (especially earlier notes), but I will try to follow it more closely in the future.

ObjectNotationExplaination
scalarScalars are represented in lower-case letters
vectorVector (and vector-value functions) are represented in bold letters (there are some exceptions, like gradient is often written as something like )
normalized vector
matrixMatrices are represented as upper-case letters
pointPoints are also represented as upper-case letters