Gaman is the third letter of the Samaritan alphabet and carries the numeral value three. It writes a plain g, and its name is the inherited Northwest Semitic one that stands behind Hebrew gimel. The gloss usually attached to that name, a camel, is worked backwards from the word rather than recorded by any ancient writer, and the atlas marks it as a reconstruction.
The letter is written as a single free-standing shape. Samaritan letters never join, so gaman looks the same beside any neighbour, and the script has no cursive in the sense that Arabic does. It also has no final form, so the letter is identical wherever it stands in a word. Between them those two facts make Samaritan an unusually predictable script for a beginner: once you know twenty-two shapes you know every shape the script will show you, which is not true of Hebrew, Arabic or Greek.
Its afterlife outside the Semitic world is worth following. Greek took the sign as gamma. The Etruscans and then the Romans took it from Greek, and in Latin it settled as the letter C, which is why the Latin alphabet has C in third place where the Semitic and Greek alphabets have a g. The letter G was cut later out of C to restore the distinction that had been lost along the way. So the Samaritan third letter and the Latin third letter are the same inherited sign, with a change of sound in between.
The character is encoded at U+0802.