ICU-21814 Fix small typos in docs/userguide

docs/userguide/collation/customization/index.md

@@ -232,7 +232,7 @@ It has been replaced by the maxVariable option.
 - `[normalization on]`
 
 Turns on or off the UCOL_NORMALIZATION_MODE attribute.
-If set to on, a quick check and neccessary normalization will be performed.
+If set to on, a quick check and necessary normalization will be performed.
 
 #### strength
 - `[strength 1]`

docs/userguide/dev/codingguidelines.md

@@ -540,7 +540,7 @@ u_formatMessage(...);
 ```
 
 > :point_right: **Note**: The `U_CAPI`/`U_DEPRECATED` and `U_EXPORT2` qualifiers
-> are required for both the declaration and the definiton of *exported C and
+> are required for both the declaration and the definition of *exported C and
 > static C++ functions*. Use `U_CAPI` (or `U_DEPRECATED`) before and `U_EXPORT2`
 > after the return type of *exported C and static C++ functions*.
 > 

docs/userguide/icu/design.md

@@ -694,7 +694,7 @@ In ICU4J 3.4.2 and earlier, `@draft` APIs were also marked with Java's `@depreca
 tag, so that uses of draft APIs in client code would be flagged by the compiler.
 These uses of the `@deprecated` tag were indicated with the comment “This is a
 draft API and might change in a future release of ICU.” Many clients found this
-confusing and/or undesireable, so ICU4J 3.4.3 no longer marks draft APIs with
+confusing and/or undesirable, so ICU4J 3.4.3 no longer marks draft APIs with
 the `@deprecated` tag by default. For clients who prefer the earlier behavior,
 ICU4J provides an ant build target, `restoreDeprecated`, which will update the
 source files to use the `@deprecated` tag. Then clients can just rebuild the ICU4J

docs/userguide/icu4c/build.md

@@ -517,7 +517,7 @@ This section will explain how to build ICU on one platform, but to produce binar
 
 Normally, in the course of a build, ICU needs to run the tools that it builds in order to generate and package data and test-data.  In a cross compilation setting, ICU is built on a different system from that which it eventually runs on. An example might be, if you are building for a small/headless system (such as an embedded device), or a system where you can't easily run the ICU command line tools (any non-UNIX-like system).
 
-To reduce confusion, we will here refer to the "A" and the "B" system. System "A" is the actual system we will be running on - the only requirements on it is are it is able to build ICU from the command line targetting itself (with `configure` or `runConfigureICU`), and secondly, that it also contain the correct toolchain for compiling and linking for the resultant platform, referred to as the "B" system.
+To reduce confusion, we will here refer to the "A" and the "B" system. System "A" is the actual system we will be running on - the only requirements on it is are it is able to build ICU from the command line targeting itself (with `configure` or `runConfigureICU`), and secondly, that it also contain the correct toolchain for compiling and linking for the resultant platform, referred to as the "B" system.
 
 The autoconf docs use the term "build" for A, and "host" for B. More details at: [http://www.gnu.org/software/autoconf/manual/html_node/Specifying-Names.html](http://www.gnu.org/software/autoconf/manual/html_node/Specifying-Names.html#Specifying-Names)
 

docs/userguide/icu_data/buildtool.md

@@ -214,7 +214,7 @@ contain numbers.  Expect to spend a fair bit of time debugging your feature
 filter to get it to work the way you expect it to.
 
 The data for many ICU features live in individual files.  The ICU Data Build
-Tool puts puts similar *types* of files into categories.  The following table
+Tool puts similar *types* of files into categories.  The following table
 summarizes the ICU data files and their corresponding features and categories:
 
 | Feature | Category ID(s) | Data Files <br/> ([icu4c/source/data](https://github.com/unicode-org/icu/tree/main/icu4c/source/data)) | Resource Size <br/> (as of ICU 64) |

docs/userguide/io/ustdio.md

@@ -14,7 +14,7 @@ License & terms of use: http://www.unicode.org/copyright.html
 This API provides a `<stdio.h>`-like API wrapper around ICU's other [formatting
 and parsing](../format_parse/index.md) APIs. It is meant to ease the transition of adding
 Unicode support to a preexisting applications using stdio. The following is a
-small list of noticable differences between stdio and ICU I/O's ustdio
+small list of noticeable differences between stdio and ICU I/O's ustdio
 implementation.
 
 *   Locale specific formatting and parsing is only done with file IO.