when to use sparse categorical cross entropy, binary code example

Example: sparse categorical cross entropy python

# example
model = Sequential([
    Dense(16, input_shape=(1,), activation='relu'), # the relu activation takes the max between 0 and x
    Dense(32, activation='relu'),
    Dense(2, activation='sigmoid'), # the sigmoid activation convert the number into number between 0 to 1
])

# the loss function is the sparse categorical crossentropy
model.compile(Adam(lr=0.001), loss='sparse_categorical_crossentropy', metrics=['accuracyt'])