hi bro, i am a bit confused here. may i ask a few question?

there are 2 ports, 1 In and 1 Out. means that the Out is for plug in headphone? and In is for plug in 3.5 male - 3.5 male between amplifier and music player?

the amplifier package include what other items beside the amplifier itself?

i am totally noob in audio stuff, sorry.....