As cameras technology has allowed us to increase the resolution of the images we capture and video we watch, so has the bandwidth required to transfer that imagery. In space, the amount of data that can be sent is currently limited due to the radio frequency (RF) systems being relied upon.
NASA is trying to fix that limitation by testing a new communications system called a Laser Communication Relay (LCR). LCR is a desirable replacement because the optical/laser communication system (lasercom) allows for much higher data transfer rates while retaining the same size, weight and power requirements of existing RF systems. What that also means is a smaller optical system can still transmit at a decent data rate too, but save on power, weight, and size on board a satellite.
The difference in data rates is quoted as being as much as 100x that of existing RF systems and is the equivalent of trying to transfer data over broadband compared to Wi-Fi. The example NASA gives is the Mars Reconnaissance Orbiter (MRO) which manages a 6Mbps data rate. The lasercom system would increase that to 100Mbps, meaning a high resolution image would arrive on Earth in 5 minutes rather than the current 90 minutes MRO takes.