Sune
The algorithm, how to recognise it and how to practise it without cheating.
Recommended algorithm
R U R' U R U2 R'7 moves · R and U only
How to recognise it
Only one corner shows yellow on top. Hold it at front left: the front-right corner's yellow sticker faces you.
Its inverse is another case
Do the Sune algorithm backwards, R U2 R' U' R U' R', and you are solving Antisune.
That's why CubeDojo never scrambles Sune that way: it builds a random state with the case fixed, so you practise Sune and not Antisune.
Practise Sune now
Random-state scrambles, a timer and spaced review. Free, on the web and on your phone.