Plus Sign + depicts the operation of addition. It looks like a small cross vertically standing in the middle of the line. Similar Unicode characters are [U:00B1], [U:2213], [U:2795], [U:2A72].

"Plus" is translated to Latin as "more." The first use of this symbol was noticed in 1489. It was Johann Widman who mentioned the plus sign for the first time in his commercial treatise to illustrate some kind of increase.

You can find this symbol in Unicode here [BLOCK:basic-latin]. Other mathematical operators are located in the following blocks: [BLOCK:mathematical-operators] and [block:supplemental-mathematical-operators].