Oh, how the mongrelization of the English language occurs under the very noses of its own native speakers!
"There's" is the contraction for "there is." But there's something quite amiss, grammatically, with the contraction "there's" when used to refer to something plural. It's just plain wrong. It's bad English, yet it is all-pervasive. Tune into your radio or TV (at your own risk) or your computer and you will hear media people, and even supposed educated people, making this grammatical error.
"There's lots of things wrong..."
"There's many people who...."
"There's three groups that..."
Wrong, wrong, and wrong again. Why aren't people contracting "there are" to "there're" when referring to more than one something or other? Even though it's an acceptable contraction, perhaps "there're" is too growly to say. If so, then don't make the contraction at all; say it correctly this way:
This is one time in the English language when a speaker must think ahead and look to the number of items being referred to in order to determine whether to use "there is" (there's, for something singular) or "there are" (there're, for something plural). Still, for reasons that completely baffle me, this one grammar error has become ubiquitous. As is very likely the concern of other grammar sticklers, it worries me that it will come to be accepted as a correct alternative simply because so many people are making the error.
Horrific, really. It grates on the ear -- as bad as hearing someone say "eck setra" instead of the proper Latin, "et cetera" ("and / other things").