Comic book publishers / series usually have some kind of compilation eventually.
IDW then, it isn't a surprise has produced "The IDW Collection 01" for Sonic. The difference is though, that instead of the usual 'trade' type, this is a larger size (than the comic books themselves) hard cover item. It contains "Volumes 1 to 3", but does that mean collections 1 through 3 or issues 1 through 3? It's about 50 dollars on Amazon though...so hopefully the answer is that it has 3 collections worth inside to justify the price.
The cover is a close up portrait of Sonic which has his ear a bit close to his eye and is meant to look somewhat-cg although it is not. There's obviously plans for more with the '01' there at the end. Compilations (and special ones like this) are always generally a good idea so that fans can collect things they missed or avoid problematically-expensive issues. You can write in for credit if you get this and know what is inside.