比如26型、45型，以及后面计划建造的是83型，这个型号数字是怎么来的？
1X型是反潜舰（ASW）
4X型是防空（AAW）护卫舰（驱逐舰）
6X型是对空引导（ADW）护卫舰（驱逐舰）
8X型是多用途舰。
这么规定，就是为了以一个2位的数字，来表示4种驱护舰。至于为什么英国会区分驱护舰的种类，一来这是种传统，或者说中二病，显得自己专业。英国自古以来在海军方面就有独领风骚的传统。长久以来，英国海军造什么船，采取什么制度，世界各国就跟着学。比如五级护卫舰，三级战列舰，无畏舰，超无畏舰等等。都是英国先造出来，其他国家说，哇，原来还有这种操作！！！教练，我想要这个！其他国家纷纷效仿。二来，站在实用主义的角度说，这是向金钱低头的结果。英国战后毕竟不能像美国那么财大气粗，把武器为了方便而通用化——万金油的佩里+斯普鲁恩斯的组合。英国为了省钱，以最小的预算达到对大的战斗力，给驱护舰做了专业划分，试图在最需要的地方派遣最合适的舰种。麻烦就麻烦些了，勒紧裤腰带过日子吧。
结果往往是事与愿违的。且不论42型（防空驱逐舰）在英阿冲突中被阿根廷航空兵干掉2艘，防空舰被飞机单机干掉，那你还防谁啊。后来因为经费不足，实际上很多舰艇处于趴窝状态。如果你的舰艇是多用途化的，那么你剩下的几艘可出动的舰艇可以执行多种任务，面对各种情况。而现在是4种专业化的舰艇，要是有一种舰艇数量太少，那海军的能力就瘸腿了。这也是因为，二战刚结束时，估计那时候的英国也想不到，50年后自己会连4种驱逐舰都凑不齐。
顺带一说，以现在的现状，护卫舰、驱逐舰、巡洋舰没什么区别，谁造的谁命名。什么谁吨位大谁吨位小已经成了无稽之谈。护卫舰（Frigate），驱逐舰（Destroyer）巡洋舰（Cruiser）的划分已经越来越模糊。比如德国7300吨的巴登-符腾堡级是护卫舰，美国9800吨的提康德罗加级是巡洋舰。日本甚至日文全都叫护卫舰，同时却使用驱逐舰的英文简称。比如接近2万吨的日向级直升机护卫舰。但是代号却用的是DDH（Hyūga-class helicopter destroyer ，ひゅうが型护卫舰, 罗马音Hyūga-gata-go-ei-kan)日文汉字名字叫“护卫舰”，英文名却是destroyer。
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11-30型，反潜艇护卫舰
Type 11 : Diesel powered anti-submarine frigate based on hull of Type 41 / 61. Not built.
Type 12 Whitby : Steam powered, high-speed "first-rate" anti-submarine frigate.
Type 12M Rothesay : Modified Type 12 design.
Type 12I Leander : Improved Type 12, general purpose frigate.
Type 14 Blackwood : Steam powered, high-speed, "second-rate" anti-submarine frigate.
Type 15 : High-speed anti submarine frigate, full conversion of wartime destroyer hulls of the "R" class.
Type 16 : High-speed anti submarine frigate, limited conversion of wartime destroyer hulls of the "T", "O" and "P" classes.
Type 17 : "Third-rate" anti-submarine frigate, analogous to wartime corvettes. Design abandoned in 1953. Not built.
Type 18 : High-speed anti submarine frigate, intermediate conversion of wartime destroyer hulls of the "N", "S", "T" and "Z" classes (and intended to replace the Type 16). Design abandoned in 1953. Not built.
Type 19 : Very high speed (42 knot) gas turbine powered anti-submarine frigate. Design abandoned in 1965. Not built.
Type 21 Amazon: General purpose, gas-turbine powered commercially designed frigate.
Type 22 Broadsword : Large, gas-turbine powered, anti-submarine frigates.
Type 23 Duke : Gas-turbine and diesel powered, anti-submarine frigates. Smaller and less expensive than the Type 22, with similar capabilities. 16 built.
Type 24 : Cheap frigate design ("Future Light Frigate") intended for export. In RN service would have served as a towed array ASW ship. Not built.
Type 25 : More capable development of the Type 24, designed to have almost the capability of a Type 22 but at only three-quarters of the cost. Much of the thinking, including the diesel-electric machinery, went into the Type 23. Not built.
Type 26 : Global Combat Ship : First announced in March 2010, and formerly known as the Future Surface Combatant. Initial orders placed in February 2014.[2]
Type 31 : The Type 31 frigate is the proposed General Purpose frigate as set out in the Strategic Defence and Security Review 2015.[3]
Type 32 : The Type 32 frigate was mentioned recently in November 2020 as a future frigate.
41-60型，防空护卫舰/驱逐舰
Type 41 Leopard-class : Diesel powered anti-aircraft frigate built on common hull with Type 61.
Type 42(i) East coast frigate : High speed coastal escort. Not built
Type 42(ii) Sheffield-class : Gas-turbine powered, fleet area-defence anti-aircraft destroyer.
Type 43 : Large gas-turbine powered, "double-ended" (Sea Dart launchers fore and aft), fleet area-defence anti-aircraft destroyer. Project cancelled in 1981 with none built.
Type 44: A smaller version of the Type 43 with better anti-submarine capability. Cancelled.
Type 45 Daring-class : Fleet area-defence anti-aircraft destroyer to replace Type 44 project. 6 built.
61-80型，对空引导护卫舰/驱逐舰
Type 61 Salisbury : Diesel powered aircraft-direction frigate built on common hull with Type 41.
Type 62 M class : High-speed aircraft-direction frigate, full conversion of wartime destroyer hulls. Not built.
81-99，通用护卫舰/驱逐舰/
Type 81 Tribal : Single-shaft steam / gas-turbine powered general purpose "colonial" frigates.
Type 82 Bristol : Large steam / gas-turbine powered fleet anti-aircraft and anti-submarine destroyer. 1 built of 4 initially planned.
Type 83: proposed in the 2021 Defence Command Paper as the successor to the Type 45 Destroyer entering service in the late 2030s.
