It's a bit hard to see... but I think it's moss. Is there soil between the path and the house wall? If so, you're bound to get some weed or other growing there. Moss likes damp, shady areas, and also tends to colonise the ground where weedkiller like glyphosate has been used often, as it's not killed by weedkillers. You can scrape it off but you might want to decide what to use to replace it, otherwise bigger weeds might take up residence...
Since 2019 I've lived in east Clare, in the west of Ireland.
There is soil there, plus it's all over an area that has stone chippings laid on top of soil as well making it hard to remove by hand unless I take all the stones off the soil, remove all the weed and then put all the stones back again, and then repeat at least once every year probably! I'l try Glyphosate as advised in the RHD link supplied. Thanks for the help!
Posts
https://www.rhs.org.uk/advice/profile?pid=348
Gardening in Central Norfolk on improved gritty moraine over chalk ... free-draining.