This plan covers:
4K monitors and TVs are the modern standard in high-end display technology, featuring four times more pixels than standard 1080p HD displays.
Although 4K was previously an expensive investment, modern 4K displays have become increasingly affordable and often beat their 1080p counterparts in terms of value for the price. This makes 4K TVs and monitors a much more attractive option for the average consumer, bridging the gap between high resolution and affordability.
Upgrading to 4K does not mean you must use 4K-supported content or devices either, as all 4K monitors are capable of outputting any resolution up to 3840x2160 including 1080p and 1440p. 1080p monitors on the other hand are technically capable of displaying 4K content as well, however, the video data is downscaled to fit the smaller resolution and does not increase the amount of pixels displayed on-screen.
The resolution of your monitor can be found in your computer's display settings, usually listed as the "native resolution" or found in the owner's manual.