8 ball... Corner Pocket.
Current seams are formed along the banks when there is a rock point or change in the bank structure. These current seams are often great places to find fish because they funnel food into a defined location. Trout sit on the soft, or "bank-side", of these current seams, picking food off as it floats by.
So what is an "Inside Corner Pocket" you ask?
It is a term I call the very upper pocket on the bank-side of a current seam as it breaks off the shore or rock point.
A lot of anglers miss the very upper part of the seam where the current initially breaks off the bank. This often overlooked "nook" or pocket can be one of the most prime spots in the seam and can yield some of the biggest, most dominate fish.
When floating rivers, pay attention for current seams breaking off the bank and position the boat and cast accordingly to give yourself enough time to land your fly into the upper most, inside, pocket of the current seam. Same things goes for wade fishing, you can work those current seams just keep working them all the way up to the very point in which they break off the bank.
Tip - You don't want your fly to land in the dead water on the inside of of the seam (unless you are ripping streamers from the boat). The trick is to land the fly into the soft (slower) currents on the bank-side of the seam... right as the current line begins to form.