在鐵道文化發達的國家，雖然鐵路系統中不同路線規格繁多，可以提供不同速度的服務。但是如果在能夠在同一條線路上提供不同等級的服務，不但能夠給予乘客多種選擇，增加旅途彈性及轉車的便利外，也可以將一條低規格的鐵道發揮最大的效率，減低運輸成本，並將國家的鐵道網帶入城市中。此舉可以避免需要利用道路或地鐵往來鐵路車站，也可以促進公共運輸導向型開發，可持續地發展寶貴的土地資源。優等列車不但允許乘客舒適地往來其他鐵路為骨幹的發展區域，特別具備地方特色的列車帶動當地文化發展。增加公共交通使用率，社會任何階級的人士從而在列車上彼此連結，為和平高效率的社會建立基礎。

在日本，無論在繁華都市的樞紐車站，例如新宿站，或者在光輝年代已過的小市鎮，例如速星站，也能夠透過不同的列車等級迅速抵達國家的其他車站。發達的鐵路網絡，幹線的多重復線建設以及極高效率的營運與時間表促使日本能夠在有限空間與資源下，依舊提供世界領先的服務。雖然新幹線的建設將全國絕大部分的旅程所需時間置於一日，但單靠高速鐵路絕對無法完全發揮鐵路的優勢，所以必須有在來列車的配合才能完善全國的鐵路網絡。新宿站一日處理的乘客人次超越三百六十萬。相比之下，春運高峰時，位於中國上海的所有國鐵車站合計僅一日處理約八十四萬人次，當中最繁忙的虹橋站處理當中約一半的乘客。從此可見，鐵路系統的多樣性，列車的有效分類以及高效率的營運對於鐵路與社會的發展極具影響。

以下文章將會簡單介紹日本旅客鐵路在來線路上的列車等級。雖然日本私有的鐵路也具有相似的分類，唯不同鐵路有對於相同分類有不同的意思，不適宜以偏概全，因此不會在此解釋。新幹線屬於特別的“超級特別急行列車”的等級，將會在未來分開詳細説明。本篇的資訊在二零二五年四月編寫。

In a country where railways culture flourishes, the variety of lines and standards paves the way to operations with a variety of speeds. A rail line that provides multiple levels of services not only gives passengers a variety of choices and flexibility in their travels, it also eases their transfers when one is needed, and maximizes the capacity and comfort of a line built to lower standards, hence reducing the cost to operate transit, allowing railways to be brought into cities and towns alike. These lower standard lines can minimize building stations far from cities centers, necessitating a transfer to road vehicles or metros. Different service levels promotes transit-oriented development and the sustainable development of valuable real estate. Express trains not only give passengers comfort between major transit development areas, but also could play host to local culture and specialties. Increasing public transit utilization connects people in different classes of society, laying the foundation for a harmonious efficient society.

In Japan, from the bustling hub stations such as Shinjuku, to the weaning industries of sunset towns like Hayahoshi, there exists different levels to train services, which makes journeys to and from the remainder of the country convenient. A diverse and resilient rail network, the duplication of rail lines, and highly optimized operations and timetables allows Japan to operate unparalleled services on limited space and infrastructure. Even as the Shinkansen connected the majority of Japanese cities within one day, no rail system can flourish by high speed rail alone, and must be integrated with efficient conventional rail to become a true network. Shinjuku alone handles over 3.6 million passengers per day. In comparison, in the peak of the spring festival migration, national rail stations in Shanghai, China combined only handles 840 thousand passengers per day, of which half was processed by Hongqiao Station. Hence, diversity in rail services, and efficient classification of trains brings enormous impact to the rails and society as a whole.

This article will briefly explore the rail service classifications that you may find on JR. Although private railways in Japan utilize similar classifications, different company uses the same classification differently, and hence it is difficult to say anything meaningful in general about them. Shinkansen belong in a special “Super Express” category, which is a topic for another time. The contents of this article is accurate at the time of writing in 2025 April.