diff --git a/handbook/essentials.html b/handbook/essentials.html
index 11c3cc768..d07707192 100644
--- a/handbook/essentials.html
+++ b/handbook/essentials.html
@@ -30,7 +30,7 @@
 <p>There is no such thing as a quick installation procedure for iPhones. The prefered app is gaia GPS.</p>
 <p><b>If the quick start doesn't work for you, go to the <a href="#general">general instructions</a> further down this page.</b></p>
 <h2>GPS for prospecting</h2>
-<p>When using your phone for prospecting for new caves, or refinding old entrances, there are two further usefull files that you should consider downloading:</p>
+<p>When using your phone for prospecting for new caves, or refinding old entrances, there are two further useful files that you should consider downloading:</p>
 <ul>
   <li><a download href="gps-essentials/entrances2024.gpx">entrances2024</a> - location of all known cave entrances.</li>
   <li><a download href="gps-essentials/kataster-boundaries-as-tracks.gpx">kataster-boundaries-as-tracks</a> - these are <b>not paths</b> but separate areas with