what's the difference between ferrite bead and inductor.

[shemo]

I heard people say ferrite bead is like an inductor (common mode choke) with inductance but it usually come is like discrete element(surface mount). I don't see any coil winding. No winding then how it could generate magnetic flux?

Inductor is a coil winding that when electricity flow through it generate magnetic flux.

 

[red_alert]

https://en.wikipedia.org/wiki/Ferrite_bead

 

[FvM]

I presume you are asking about chip ferrite beads that aren't addressed in the linked Wikipedia article.

Ferrite beads are generally lossy inductors. Chip ferrite beads are mutilayers of ferrite and metal. For higher Z numbers, the metal is structured to form planar windings. In so far there may be "windings" hidden in the chip.

 

[malli_1729]

Check any sample inductor and Ferrite bead data sheets. Especially their impedance curves. Any Normal Inductor will be inductor only up to a range of frequencies. After that they will behave as Capacitors ( Impedance reduces w.r.t Frequency). Ferrite bead will behave like resistor after certain frequency range. Based how much attenuation required and frequency range to be attenuated, You can select the Ferrite beads.
http://lpvo.fe.uni-lj.si/fileadmin/files/Izobrazevanje/RES/Gradiva/07/Ferrite beads.pdf
see the 3rd page for impedance characterstic and how signal behaves......