I have certain apps, like Google Maps, on my phone which I am unable to move to my SD card from the internal memory. I tried moving it from the App management menu in Phone settings, but the move to SD card option isn't enabled. Is moving these apps going to affect the working of the device?
You are very ambiguous regarding which OS is in question. Judging from "Google Maps", I will assume it is an Android device.
Case 1: Factory apps which are pre-installed with your system can never be moved to the SD Card, as they are hard wired in the ROM. The only solution in that case is rooting the phone and replacing your ROM software. I will not explain rooting / ROM swapping here since it is an entire subject.
Case 2: Most apps installed from Play Store can be moved to the SD Card by navigating to:
Settings > Applications > Manage Applications > On SD card
(Android 2.3.6, menu may slightly vary on other versions)
You will be able to check / uncheck the apps that you'd like to move to the SD Card. Most apps will allow you to move them, but some apps will not. Once again, rooting resolves this.
Note: Pre-installed apps which have been updated through Google Play Store behave like in case 2, because the updated version does not reside in the ROM.