That is an HDD, ie, a Hard Disk Drive. 1 TB of course means the capacity (ie, size), 7200-rpm means the rotational speed of the platter/platters (7200 revolutions per minute), and SATA means the connectivity.
For an SSD drive, size and connectivity "parameters" mean the same, but the "speed" is measured in terms of Read and Write speeds. SSDs don't have platters inside of them, The technology is different. But they are definitely faster than HDDs.
Update: OK, I found this:
https://everymac.com/systems/apple/...-inch-aluminum-how-to-upgrade-hard-drive.html
I suspect your iMac has "SATA 2.0" connectivity. I believe you can use an SSD that has SATA 3.0 connectivity would be OK, but of course the "speed" between the SSD and that part of your Mac will be at the lower, SATA 2.0 levels. However, within that link is this:
"OWC also
discovered that the "Late 2009" -- and subsequently introduced "Mid-2010" -- models use a "connector that seems to use the drive's internal sensors" rather than an external sensor like earlier 20-Inch and 24-Inch Aluminum iMac models.
Originally, this meant that the most straightforward way to upgrade the hard drive was to "replace the drive with another model from the same manufacturer that [OWC or another third-party has] confirmed works properly with this thermal sensor cable". OWC provides a
list of compatible drives. Readers also shared
reports that taping an external temperature sensor to a hard drive or SSD that does not have an internal sensor will work in these models, but this method is risky.
Thankfully, though, OWC subsequently developed a custom digital monitor that "talks Apple SMC" and "maintains proper temperature reporting and Apple Diagnostic compatibility" for these models and sells it as part of convenient
SSD Upgrade DIY Kits. Although it still is fine to replace the hard drive with another model from the same manufacturer, this OWC solution provides many more options"
So, not sure how "simple" this would be. I also do not know your
exact mid 2010 iMac model. According to all that above, that is important.
Maybe someone with more expertise can "chime in" on this discussion.