I have seen the example of the blue symbol in the picture in some advertisements. This symbol is used to add an extra word in the middle of a sentence. However, I have searched a lot, but I was not able to find the name of this symbol in English.

I have seen the example of the blue symbol in the picture in some advertisements. This symbol is used to add an extra word in the middle of a sentence. However, I have searched a lot, but I was not able to find the name of this symbol in English.

The inverted caret symbol is sometimes named as caron, though this is in the context of a diacritic mark rather than a proof reading mark.
That is intended to mimic a proofreader's mark. According to Wikipedia this particular mark is a caret.