【中文版】

Yen是日元，是日本官方货币的称呼。日元是日本国内唯一的流通货币，也是全球主要货币之一。日元的面值有1000、500、100、50、10、5、1元等，使用时按照面值进行计算。

日元作为日本的货币，具有以下特点：

1. 日元是可自由兑换的货币，可以方便地在国际上进行贸易和投资活动。
2. 日元是日本的经济命脉之一，对日本的进出口贸易和国内经济运行具有重要作用。
3. 日元是日本的主权货币，日本政府对日元的发行和流通具有调控权。
4. 日元是亚洲主要货币之一，可以在亚洲范围内进行贸易和投资活动。

日元在历史上曾经经历过多次贬值和升值，其中在20世纪90年代后期，由于日本经济泡沫破裂，日元一度贬值至接近1美元对140日元的历史低点。但随着日本经济的复苏和全球经济的增长，日元逐渐升值，目前大约在1美元对110日元左右的水平。

总之，日元是日本的官方货币，也是全球主要货币之一，具有自由兑换、重要经济作用、主权调控等特点。

【英文版】

Yen is the official currency of Japan, also known as the Japanese yen. The yen is the only circulating currency in Japan and also one of the major currencies in the world. The denominations of the yen include 1000, 500, 100, 50, 10, 5, and 1 yen, and the value is calculated based on the denomination.

As Japan's currency, the yen has the following characteristics:

1. The yen is a freely convertible currency that can be easily used for international trade and investment activities.
2. The yen is one of the lifelines of Japan's economy and plays an important role in Japan's import and export trade and domestic economic operations.
3. The yen is Japan's sovereign currency, and Japan's government has control over the issuance and circulation of the yen.
4. The yen is one of the major currencies in Asia and can be used for trade and investment activities within the region.

The yen has experienced several devaluations and appreciations throughout history. In the late 1990s, due to the bursting of the Japanese economic bubble, the yen briefly depreciated to a historic low of nearly 1 US dollar to 140 yen. However, with Japan's economic recovery and global economic growth, the yen gradually appreciated and is currently around 1 US dollar to approximately 110 yen.

In summary, the yen is Japan's official currency and one of the major currencies in the world, characterized by its free convertibility, important economic role, and sovereign control.