When does $d$ mean a differential and when does it mean a derivative?
100283
How to understand the notion of a differential of a function
51253
Graphical intuition behind directional derivative interpreted as a(∂f/∂x)+b(∂f/∂y), where  is directional vector of unit length?
95400
Different definitions of exterior derivative
84984
What does $\partial_{\mu}$ mean?
1246
Differences between derivatives and strong derivatives
33691
Confusion about a particular differential form being exact?
66433
Derivative of delta function
16291
Discontinuous derivative.
75168
Exact Differentials
151314
What does it mean to differentiate in calculus?
134871
Using definition of derivative to differentiate $f(x)= \sqrt{x}+1$
140884
Limits and derivatives - two questions
56424
Using D to find a symbolic derivative
155509
Does a linear operator obeying Leibniz rule imply it is a differential operator?
36826
Products of Differential Operators
71726
When can we not treat differentials as fractions? And when is it perfectly OK?
56429
Extension of partial derivatives and the definition of $C^k(\overline{\Omega})$