The former takes money from the wealthiest estates involuntarily and uses it to help fund government programs. The latter are entities that people voluntarily give money to, in support of causes that they think benefit society.
However, the two are very much related, as Bloomberg discusses in "GOP Plan to Kill Estate Tax Sets Up Charitable Giving Conflict."
The issue is that one of the most common ways to get around the estate tax is to shrink an estate to just below the estate tax exemption limit. A great way to do this is to give money to charity.
When the estate tax was temporarily eliminated in 2010, charitable giving was reduced by 37%.
This has many charities very nervous about the possibility that the estate tax could be eliminated again, as the Trump administration and Congressional Republicans would like.
Republicans are looking for ways to get around this problem by finding other ways to encourage
It is not yet certain whether they will have the votes necessary to do that.
It is also not certain at this point whether they will have the votes to eliminate the estate tax either.
Reference: Bloomberg (Aug. 25, 2017) "GOP Plan to Kill Estate Tax Sets Up Charitable Giving Conflict."