In general, more pixels mean a sharper picture. A Full HD TV should now be considered the minimum standard. A 4K TV will give you a much-improved picture, especially on a larger screen - provided you have 4K content to play on it. 8K TVs are the next advance, and a great choice if you want your TV to be as future-proof as possible.
An OLED TV will give you great colours, contrast and deep blacks. They're also very energy-efficient, but larger screen sizes can be expensive. QLED TVs don't offer quite the same levels of colour or contrast, but they are super-bright and generally better value for a bigger screen. NanoCell is an LG technology that offers similar benefits as QLED. LED and LCD TVs aren't quite as cutting-edge, but they're still good all-rounders, especially on a budget.
HDR stands for High Dynamic Range. It gives a truer, wider range of colours plus improved contrast. There are two current standards, HDR10 and HDR10+. Dolby Vision is a similar technology that can give even better picture in certain situations. To gain the benefit of HDR or Dolby Vision, you'll need to be watching content created specially with these technologies in mind.
Instead of using a dongle or set-top box, Smart TVs have their brains built-in. Just connect them to your home Internet and you can stream from your favourite media apps like Netflix or Prime Video. Some Smart TVs also include voice assistants like Google Assistant or Alexa.
TV screen sizes are given in inches. They're measured diagonally from top corner to the opposite bottom corner and don't include the frame of the TV. Think about the size of your room and how far back you'll be sitting from the screen. Smaller TVs are great in kitchens or bedrooms, but you might want a screen 55 inches or more to give a cinematic living room experience.
These are the 'free' digital TV services available in Ireland and the UK. They both use a similar technology, so a Freeview HD TV will usually be able to receive a Saorview signal when connected to a suitable aerial. If your TV signal comes through a set-top box, you don't need to worry about Freeview and Saorview.