For what are input scripts?

[Frodek]

Inputs script are usually bigger than output scripts. Only take place in blocks.

[franky1]

in very simple terms

input contain transaction ID's and other data to locate where the funds came from. (lots of bytes needed) (plus value)
also requires signatures, which add on extra bytes to an input.

outputs are just destination addresses (not so many bytes) (plus value)

however output scripts can vary in length too if they are including contract conditions. but generally a input is longer than output due to need of more data to locate source of funding and show proof its spendable

however the input bytes:output bytes ratios will change once future features are part of bitcoin

[Frodek]

But inputs records contains hash of previous transaction. Input script are difficult to analyze.

[franky1]

But inputs records contains hash of previous transaction. Input script are difficult to analyze.

i was speaking more in general about input vs output. in previous post.

however the "scripts" area of an input is usually the signature

this will however change a bit if/when segwit activates and people use segwit style transactions