I'm looking through the Android Open Source Project makefiles, and I'm seeing what appears to be two different ways of including another makefile. For example, `master/build/target/product/aosp_arm64.mk` has these lines:

```
PRODUCT_COPY_FILES += frameworks/native/data/etc/android.hardware.ethernet.xml:system/etc/permissions/android.hardware.ethernet.xml

$(call inherit-product, $(SRC_TARGET_DIR)/product/core_64_bit.mk)
$(call inherit-product, $(SRC_TARGET_DIR)/product/aosp_base_telephony.mk)
$(call inherit-product, $(SRC_TARGET_DIR)/board/generic_arm64/device.mk)

include $(SRC_TARGET_DIR)/product/emulator.mk

PRODUCT_NAME := aosp_arm64
PRODUCT_DEVICE := generic_arm64
PRODUCT_BRAND := Android
PRODUCT_MODEL := AOSP on ARM arm64 Emulator

```

What is the difference(s) between the `$(call inherit-product ...)` line and the `include ...` line?