The lesser curvature of the stomach, extending between the cardiac and pyloric orifices, forms the right or posterior border of the stomach.

It descends as a continuation of the right margin of the esophagus

Esophagus

The esophagus is an organ in vertebrates which consists of a muscular tube through which food passes from the pharynx to the stomach. During swallowing, food passes from the mouth through the pharynx into the esophagus and travels via peristalsis to the stomach...

 in front of the fibers of the right crus of the diaphragm, and then, turning to the right, it crosses the first lumbar vertebra and ends at the pylorus

Pylorus

The pylorus is the region of the stomach that connects to the duodenum . It is divided into two parts:* the pyloric antrum, which connects to the body of the stomach.* the pyloric canal, which connects to the duodenum....

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Nearer its pyloric than its cardiac end is a well-marked notch, the incisura angularis, which varies somewhat in position with the state of distension of the viscus; it serves to separate the stomach into a right and a left portion.

The lesser curvature gives attachment to the two layers of the hepatogastric ligament

Hepatogastric ligament

The cranial part of the lesser omentum is formed by the hepatogastric ligament , extending between the liver and stomach. The ligament itself consists of a dense cranial portion and the caudal portion...

, and between these two layers are the left gastric artery

Left gastric artery

In human anatomy, the left gastric artery arises from the celiac artery, and runs along the superior portion of the lesser curvature of the stomach. Branches also supply the lower esophagus...

 and the right gastric branch of the hepatic artery.