Quelque chose, something, refers to a non-living thing. The logic in this is the same as in quelqu' un (see previous chapter). It can refer to something unknown or to a not further defined element of a group.
Il y a quelquechose de bizarre là dedans.
= There is something strange in it.
Il y a quelqueschoses que je n' aime pas du tout. = There are some things I do not like at all.