# What is the point of path integral for boson and fermion?

I am a beginner to study QFT and confused about path integral for boson or fermion.

I have read about the path integral for single particle, and finished some problems. But I cannot understand the next chapter which is about path integral for boson and fermion.

Here, I am confused for a long time. Could you please tell me the difference between the two kind of path integrals? What is the point of path integral for boson and fermion?

I find that there are big differences in forms between single particle, boson and fermion. I am not understand why the book uses different forms to discuss them. Even the path integral for the spin system has a new form to discuss.

In my opinion, I think the biggest difference between single particle and boson (fermion) is statistics, but how to consider about the statistical properties in path integral? Just using one symbol for differential, $D$, to take the place of the original symbol, $d$, is enough?

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are you really asking about the difference between quantum mechanics and QFT? and what book? –  BjornW Feb 6 at 9:57
I am asking about QFT, I am confused about path integral for bosons and Fermions. I cannot understand the formula and I want some help. Btw, the book is QFT in condensed matter physics, by N. Nagaosa, a very brief book. Maybe it is not a good book for a beginner, and I also know many other books, but I just have this one book on my hand to read. –  qfzklm Feb 6 at 12:56