I ordered an IR pair of components from Amazon and received this which I do not think is an IR emitter or receiver. Does anyone have any ideas to what this component is? I could not find anything by searching.
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\$\begingroup\$ Your link doesn't work for me. Also, the post editor has a way to add images that will be hosted here (via Imgur), rather than an another external site. \$\endgroup\$– uint128_tMay 2, 2017 at 4:07
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That is an LDR. A Light-Dependent Resistor. It is used mostly in voltage-divider circuits that can detect the lowering of resistance in the presence of light.
It is not specific to IR without a filter.
You can wire it like this to detect incident light:
It looks like this wired to an Arduino Uno:
You can get the code and some discussion HERE
LDRs are handy for detecting both light and dark, which means they can be used in circuits that can turn something on when the light goes away, and vice-versa.
Here is an interesting article that discusses how to do this without a microprocessor:
The OP mentions ordering a pair of IR devices but does not say why. Note that phototransistors paired with LEDs can be used for much faster switching, like for instance data communications.
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3\$\begingroup\$ You should add that LDRs respond slowly to light making them nearly useless for communications. Just in case if that is what the OP was interested in. \$\endgroup\$– st2000May 2, 2017 at 4:57