What do each of the symbols next to the test cases mean?

I'm sorry as I know this is something I should be able to figure out by myself but I really don't even know how to correctly search for the answer, I gave up after an hour of trying to put into the right words with no results.

Anyways so basically I'm doing an assignment and we are given tests to check our code, I'm just not really sure what the symbols next to my tests mean?

https://gyazo.com/204ccaa57684fd8571989da6182a11b6

Obviously testPGCD has failed and testSimplified, testIsConstant, testGetConstant have passed with no issues.

Now here is the grey area for me:

1. what does the blue box with the cross in them mean? (testAdd, testDifferentiate)
2. what does no box at all mean? (the last 4 tests on the list)
3. what does the blue triangle (play button I think?) mean?

Again sorry for something so simple but I'm really lost!