Yamaha CLP 240 Digital Piano
Many people today, are choosing a digital piano, over the traditional acoustic piano for several reasons.

Digital pianos, are generally, cheaper, smaller, lighter, and easier to maintain than their acoustic counterparts. They never need tuning, are relatively easy to transport, and one of the greatest advantages, is that they can be played 'silently', using headphones, so that you can play and practice, at any time of the day or night, without disturbing other family members, or neighbours.

The sound quality and playability of these pianos has increased dramatically over recent years, making them a very real alternative to their acoustic cousins.

If you are considering purchasing a digital instrument, my advice would be to try as many different makes and models, as possible, as they all have slightly different characteristics. You will 'know' when a piano 'feels right' for you. Don't be pressured by the salesperson into purchasing a piano that you are not 100% comfortable with.

The main players (pun intended) in the market, are Yamaha, Casio, Roland, and more recently, Kawai.
All make excellent pianos, with varying features, and model and price ranges.
For a simple explanation of some of the sometimes, bewildering list of features digital pianos offer, please click HERE

As with most musical instuments, you get what you pay for, but be careful that you don't end up paying a premium for features, that you don't need, or probably will never use.
These features could be, hundreds of extra instrument sounds, automated drum and backing instuments, built in teaching aids (which in my experience, many people never use) multi-track sequencers, ( a sequencer, is basically software that can record your performances. A multi-track sequencer allows you to add extra instrument sounds and parts, to your recordings)
Don't forget that some dealers offer a hire service, so that you can thoroughly try out the instument, and return it, or upgrade after a fixed period of time, or purchase it outright, if you are happy with it.

So, the most basic digital pianos, consist of just a keyboard, with a limited number of sounds built in ( generally a couple of 'acoustic' pianos, basic electric pianos, organ, strings, etc. and built in speakers.
You would need to buy a stand to sit it on.
These take up very little space, are inexpensive, and ideal for those who may be unsure whether their interest in the piano, will continue long term.

At the other end of the scale, you can find the most realistic grand piano sounds, built into beautiful cabinets, that are a fine piece of furniture, in themselves. There are even traditional acoustic grand pianos, which have built in sound modules and can faithfully reproduce your performances, and also play back disks, containing pre-recorded midi files produced by professional pianists.

I imagine that most of us, would be looking at instuments somewhere in the middle of those two extremes.
Of all the makes and models available, I have had most experience with  models from Yamaha, and Roland.
In my personal opinion, Yamaha are generally better value for money, although some prefer the Roland sound.
In the end, as I said earlier, it all comes down to personal preference, and, of course, your budget.

Tips on choosing and buying a Digital Piano