Anders v. California was a court case where a man in California wanted to appeal his criminal conviction, but his lawyer said he couldn't because there were no good reasons to appeal. The man, Anders, said he wanted to appeal anyway, even if he didn't have a good reason. The court had to decide whether Anders had a right to appeal even without a good reason.
It's kind of like when you want to play a game with your friend, but your friend doesn't want to play because they think they will lose. You might say, "let's play anyway, even if I win every time." And then you have to decide if you should play or not, even if your friend doesn't want to.
In the end, the court said that Anders did have a right to appeal even if he didn't have a good reason. This was an important decision because it meant that everyone has the right to challenge their criminal conviction, even if their lawyer doesn't think they should.