Not so long ago the idea of an online degree meant you had purchased a certificate saying you had a degree in "any subject you like" from a university no-one had ever heard of. Of course no-one had heard of it - it didn't exist. You were simply paying an online scammer to print you a certificate. No studying of any kind was required. Online degrees acquired a bad press.
Potential employers aren't daft though. Most can tell the difference between a fake degree from a non-existent university and a real degree. A few pertinent questions at an interview will soon tell them whether the holder has studied for their degree or not.
The world has changed hugely in recent years. The advent of broadband has made it increasingly easy to study online. In the UK this is called distance learning - and many universities offer distance learning degrees. Some require you to attend the university from time to time, some don't.
The work that you do towards your degree will be marked by regular university tutors, just as it would if you attended classes on campus. A potential employer will be able to check with the university to assure themselves that you do truly hold one of their degrees.
The change in working patterns means that greater numbers of people wish to retrain or take up further studies. The profile of university students is changing. Thirty years ago the overwhelming majority started their studies at the age of 18. Defer this until 20 and you were considered OLD. Not now, mature students (and many are in their 40s, 50s or older) are becoming commonplace. But when you are older it's not so easy to simply give up your home life and live away from home for 6 8 months of the year. You will have financial and family commitments. Online study allows you to fit your studies around these commitments without taking a huge drop in income. You can pay your way through university without emerging with a debt that will take you the next 10 years to pay off.
The increase in the number of people studying remotely means that this is fast becoming an accepted way of gaining a degree. Don't be fooled online study is not an easy option. Yes, it has more flexibility, but it is harder to motivate yourself with no commitment to attend classes and the demands of work and family ever present. You will need to be dedicated, motivated and have good time management skills. All attributes that are valued by potential employers who will be impressed by your ability to study and manage your work/home life simultaneously.