What do these things mean when looking at My Activity in google?

[Rachel Marie via StackOverflow]

Sorry if this not a question you all normally have, but I am new the site. I am wondering what these things mean when, I came across my/ My activity for google.

com.android.mms - I thought maybe it meant message sent, and with the com.android.mms- abbreviation comes a time you accessed this source or sent or received?!?!?!?!?! So thinking that it meant you sent or received a text message, I looked in messages and times NON of them matched and I had other text messages that didn't match... SO I AM CLUELESS and very curious.. These other ones I am clueless on have not the first clue what they mean, If you can PLEASE HELP ME>>> thank you so much. com.android.incallui com.sec.tetheringprovision

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