arr = np.array([[1, 2, 3], [4, 5, 6], [7, 8, 9]])

# Fancy indexing
rows = [0, 2]
cols = [1, 2]
result = arr[rows, cols]  # [2 9] - elements at (0,1) and (2,2)

# Boolean indexing with conditions
mask = (arr > 3) & (arr < 8)  # Multiple conditions
filtered = arr[mask]  # [4 5 6 7]