Describe the Linux cache-clearing example accurately

README.md

@@ -56,8 +56,8 @@ hyperfine --warmup 3 'grep -R TODO *'
 ```
 
 Conversely, if you want to run the benchmark for a cold cache, you can use the `-p`/`--prepare`
-option to run a special command before *each* timing run. For example, to clear harddisk caches
-on Linux, you can run
+option to run a special command before *each* timing run. For example, to clear Linux filesystem caches,
+you can run
 ```sh
 sync; echo 3 | sudo tee /proc/sys/vm/drop_caches
 ```
@@ -89,7 +89,7 @@ hyperfine -L compiler gcc,clang '{compiler} -O2 main.cpp'
 
 ### Intermediate shell
 
-By default, commands are executed using `sh` on Unix (resolved through `PATH`) or `cmd.exe` on Windows.
+By default, commands are executed using a predefined shell (`/bin/sh` on Unix, `cmd.exe` on Windows).
 If you want to use a different shell, you can use the `-S, --shell <SHELL>` option:
 ```sh
 hyperfine --shell zsh 'for i in {1..10000}; do echo test; done'