Kouchi Makikomi is a throw an inner reap, while wrapping the arm and falling.
Note: current Judo rules don’t allow touching the leg, so your arm wraps the the opponent’s arm upward rather than the leg downward (see the thumbnail).
Judo is made up of throwing (nage), grappling (katame or ‘newaza’) and striking (atemi) techniques.
The throwing techniques are split into standing techniques (tachi-waza) and sacrifice [falling] techniques (sutemi-waza). In turn, the standing techniques are split into hand techniques (te-waza), hip techniques (koshi-waza) and foot techniques (ashi-waza).
See a full demonstration of different nage-waza (throwing techniques) at: https://www.youtube.com/watch?v=niPb0NBqBWA