diff --git a/src/cache.rs b/src/cache.rs
index fe29cd4..1cf0ee9 100644
--- a/src/cache.rs
+++ b/src/cache.rs
@@ -1,13 +1,21 @@
+//! This module contains the cache manager.
+
 use std::path::PathBuf;
 use std::fs::File;
 use std::io::{Write, BufRead, BufReader};
 use walkdir::WalkDir;
 use crate::{Result, GIT_DIR};
 
+/// The cache of gclone.
+///
+/// When running the command `cdg`, if the computer just booted, finding all the directories can be
+/// quite slow. The cache contains the list of entries in the git directory to avoid re-finding
+/// them every time.
 pub struct Cache(Vec<String>);
 
 impl Cache {
 
+    /// Generates the cache by traversing the files in the git directory.
     pub fn generate() -> Cache {
         Cache(WalkDir::new(&*GIT_DIR)
             .max_depth(3)
@@ -17,6 +25,7 @@ impl Cache {
             .collect())
     }
 
+    /// Reads the cache file.
     pub fn read() -> Result<Cache> {
 
         let mut path = PathBuf::from(&*GIT_DIR);
@@ -36,6 +45,7 @@ impl Cache {
         Ok(Cache(values))
     }
 
+    /// Reads the cache file, and if it failed, generate a new cache.
     pub fn read_or_generate() -> Cache {
         match Cache::read() {
             Ok(c) => c,
@@ -43,6 +53,7 @@ impl Cache {
         }
     }
 
+    /// Writes the current content of the cache to the cache file.
     pub fn write(&self) -> Result<()> {
         let mut path = PathBuf::from(&*GIT_DIR);
         path.push(".cdgcache");
@@ -55,6 +66,7 @@ impl Cache {
         Ok(())
     }
 
+    /// Search a directory in the cache, and returns all matching directories.
     pub fn find(&self, dirname: &str) -> Vec<String> {
         let dirname = &format!("/{}", dirname);
         let mut matches = vec![];
@@ -67,6 +79,7 @@ impl Cache {
         matches
     }
 
+    /// Appends a value to the cache.
     pub fn append(&mut self, value: String) {
         self.0.push(value);
     }