Update Overview.md

fix typo

docs/markdown/Overview.md

@@ -17,6 +17,6 @@ Meson follows the overall structure of other popular build systems, such as CMak
 
 The directory that contains the source code is called the *source directory*. Correspondingly the directory where the output is written is called the *build directory*. In other build systems it is common to have these two be the same directory. This is called an *in-source build*. The case where the build directory is separate is called an *out-of-source build*.
 
-What sets Meson apart from most build systems is that it enforces a separate build directory. All files created by the build system are put in the build directory. It is actually impossible to do an in-source build. For people used to building inside their source tree, this may seem like a needles complication. However there are several benefits to doing only out-of-source builds. These will be explained in the next chapter.
+What sets Meson apart from most build systems is that it enforces a separate build directory. All files created by the build system are put in the build directory. It is actually impossible to do an in-source build. For people used to building inside their source tree, this may seem like a needless complication. However there are several benefits to doing only out-of-source builds. These will be explained in the next chapter.
 
 When the source code is built, a set of *unit tests* is usually run. They ensure that the program is working as it should. If it does, the build result can be *installed* after which it is ready for use.