diff --git a/Back/skydiveLogs-api.DomainBusiness/AircraftService.cs b/Back/skydiveLogs-api.DomainBusiness/AircraftService.cs
index c26b042..db6e921 100644
--- a/Back/skydiveLogs-api.DomainBusiness/AircraftService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/AircraftService.cs
@@ -11,6 +11,11 @@ namespace skydiveLogs_api.DomainBusiness
     {
         #region Public Constructors
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="AircraftService"/> class.
+        /// </summary>
+        /// <param name="aircraftRepository">The aircraft repository for data access.</param>
+        /// <param name="cacheService">The cache service for caching operations.</param>
         public AircraftService(IAircraftRepository aircraftRepository,
                                ICacheService cacheService)
         {
@@ -22,23 +27,40 @@ namespace skydiveLogs_api.DomainBusiness
 
         #region Public Methods
 
+        /// <summary>
+        /// Adds a new aircraft to the system.
+        /// </summary>
+        /// <param name="newAircraft">The Aircraft entity containing the data for the new aircraft.</param>
         public void AddNewAircraft(Aircraft newAircraft)
         {
             _aircraftRepository.Add(newAircraft);
             _cacheService.Delete(CacheType.Aircraft);
         }
 
+        /// <summary>
+        /// Deletes an aircraft by its ID.
+        /// </summary>
+        /// <param name="id">The aircraft ID to delete.</param>
         public void DeleteAircraftById(int id)
         {
             throw new NotImplementedException();
         }
 
+        /// <summary>
+        /// Retrieves an aircraft by its ID.
+        /// </summary>
+        /// <param name="id">The aircraft ID to retrieve.</param>
+        /// <returns>An Aircraft entity containing the aircraft details.</returns>
         public Aircraft GetAircraftById(int id)
         {
             var allAircrafts = GetAllAircrafts();
             return allAircrafts.Single(g => g.Id == id);
         }
 
+        /// <summary>
+        /// Retrieves all aircrafts.
+        /// </summary>
+        /// <returns>A collection of Aircraft entities containing all aircraft data.</returns>
         public IEnumerable<Aircraft> GetAllAircrafts()
         {
             if (!_cacheService.Contains(CacheType.Aircraft))
@@ -49,6 +71,13 @@ namespace skydiveLogs_api.DomainBusiness
             return _cacheService.Get<IEnumerable<Aircraft>>(CacheType.Aircraft);
         }
 
+        /// <summary>
+        /// Updates an existing aircraft.
+        /// </summary>
+        /// <param name="id">The aircraft ID to update.</param>
+        /// <param name="aircraft">Aircraft entity containing the updated aircraft data.</param>
+        /// <param name="resetCache">Whether to reset the cache after update.</param>
+        /// <returns>True if the update was successful, false otherwise.</returns>
         public bool UpdateAircraft(int id, Aircraft aircraft, bool resetCache = true)
         {
             aircraft.Id = id;
@@ -69,4 +98,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Private Fields
     }
-}
\ No newline at end of file
+}
diff --git a/Back/skydiveLogs-api.DomainBusiness/CacheService.cs b/Back/skydiveLogs-api.DomainBusiness/CacheService.cs
index 01edbfa..f958047 100644
--- a/Back/skydiveLogs-api.DomainBusiness/CacheService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/CacheService.cs
@@ -24,24 +24,50 @@ namespace skydiveLogs_api.DomainBusiness
 
         #region Public Methods
 
+        /// <summary>
+        /// Checks if a specific cache entry exists for a given type and user ID.
+        /// </summary>
+        /// <param name="type">The type of data to check for in the cache.</param>
+        /// <param name="userId">Optional user ID to distinguish cache entries. Default is 0.</param>
+        /// <returns>True if the cache entry exists and is valid, otherwise false.</returns>
         public bool Contains(CacheType type, int userId = 0)
         {
             var key = GetKey(userId, type);
             return _memoryCache.Contains(key.ToString());
         }
 
+        /// <summary>
+        /// Removes a cache entry from the store.
+        /// </summary>
+        /// <param name="type">The type of data to remove from the cache.</param>
+        /// <param name="userId">Optional user ID to identify the cache entry. Default is 0.</param>
         public void Delete(CacheType type, int userId = 0)
         {
             var key = GetKey(userId, type);
             _memoryCache.Remove(key.ToString());
         }
 
+        /// <summary>
+        /// Retrieves data from the cache for a specified type and user ID.
+        /// </summary>
+        /// <typeparam name="T">The expected type of the cached data.</typeparam>
+        /// <param name="type">The type of data to retrieve from the cache.</param>
+        /// <param name="userId">Optional user ID to identify the cache entry. Default is 0.</param>
+        /// <returns>The cached data cast to type T, or default(T) if not found or expired.</returns>
         public T Get<T>(CacheType type, int userId = 0)
         {
             var key = GetKey(userId, type);
             return (T)_memoryCache.Get(key.ToString());
         }
 
+        /// <summary>
+        /// Stores data in the cache with a specified expiry time.
+        /// </summary>
+        /// <param name="type">The unique identifier for the cache key.</param>
+        /// <param name="value">The object data to be cached.</param>
+        /// <param name="duration">The duration in milliseconds before the cache entry expires.</param>
+        /// <param name="userId">Optional user ID to distinguish cache entries. Default is 0.</param>
+        /// <exception cref="ArgumentException">Thrown when duration is less than or equal to zero.</exception>
         public void Put(CacheType type, object value, int duration, int userId = 0)
         {
             var key = GetKey(userId, type);
@@ -56,6 +82,12 @@ namespace skydiveLogs_api.DomainBusiness
             _memoryCache.Set(key.ToString(), value, policy);
         }
 
+        /// <summary>
+        /// Generates a cache key by combining the user ID and cache type.
+        /// </summary>
+        /// <param name="userId">The user ID to include in the key.</param>
+        /// <param name="type">The cache type to include in the key.</param>
+        /// <returns>A concatenated string key combining userId and type.</returns>
         private string GetKey(int userId, CacheType type)
         {
             return $"{userId}-{type}";
@@ -63,4 +95,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Public Methods
     }
-}
\ No newline at end of file
+}
diff --git a/Back/skydiveLogs-api.DomainBusiness/DropZoneService.cs b/Back/skydiveLogs-api.DomainBusiness/DropZoneService.cs
index c598ca3..2a63c48 100644
--- a/Back/skydiveLogs-api.DomainBusiness/DropZoneService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/DropZoneService.cs
@@ -26,12 +26,21 @@ namespace skydiveLogs_api.DomainBusiness
 
         #region Public Methods
 
+        /// <summary>
+        /// Adds a new drop zone to the system.
+        /// </summary>
+        /// <param name="newdropZone">The DropZone entity containing the new drop zone data.</param>
         public void AddNewDz(DropZone newdropZone)
         {
             _dropZoneRepository.Add(newdropZone);
             _cacheService.Delete(CacheType.DropZone);
         }
 
+        /// <summary>
+        /// Adds a drop zone to the user's favorites.
+        /// </summary>
+        /// <param name="dzId">The drop zone ID to add to favorites.</param>
+        /// <returns>True if the drop zone was added to favorites, false otherwise.</returns>
         public bool AddToFavorite(int dzId)
         {
             var dzToAddToFavorite = GetDzById(dzId);
@@ -47,11 +56,19 @@ namespace skydiveLogs_api.DomainBusiness
             return result > 0;
         }
 
+        /// <summary>
+        /// Deletes a drop zone by its ID.
+        /// </summary>
+        /// <param name="id">The drop zone ID to delete.</param>
         public void DeleteDzById(int id)
         {
             throw new NotImplementedException();
         }
 
+        /// <summary>
+        /// Retrieves a list of all drop zones with favorites status.
+        /// </summary>
+        /// <returns>A collection of DropZone entities containing all drop zones with their favorite status.</returns>
         public IEnumerable<DropZone> GetAllDzs()
         {
             var results = Enumerable.Empty<DropZone>();
@@ -78,12 +95,22 @@ namespace skydiveLogs_api.DomainBusiness
             return results.ToList();
         }
 
+        /// <summary>
+        /// Retrieves a drop zone by its ID.
+        /// </summary>
+        /// <param name="id">The drop zone ID to retrieve.</param>
+        /// <returns>A DropZone entity containing the drop zone details.</returns>
         public DropZone GetDzById(int id)
         {
             var allDzs = GetAllRefDzs();
             return allDzs.Single(g => g.Id == id);
         }
 
+        /// <summary>
+        /// Removes a drop zone from the user's favorites.
+        /// </summary>
+        /// <param name="dzId">The drop zone ID to remove from favorites.</param>
+        /// <returns>True if the drop zone was removed from favorites, false otherwise.</returns>
         public bool RemoveToFavorite(int dzId)
         {
             var result = _favoriteDropZoneRepository.Delete(dzId, _identityService.ConnectedUser.Id);
@@ -92,6 +119,13 @@ namespace skydiveLogs_api.DomainBusiness
             return result > 0;
         }
 
+        /// <summary>
+        /// Updates an existing drop zone.
+        /// </summary>
+        /// <param name="id">The drop zone ID to update.</param>
+        /// <param name="dropZone">DropZone entity containing the updated drop zone data.</param>
+        /// <param name="resetCache">Whether to reset the cache after update.</param>
+        /// <returns>True if the update was successful, false otherwise.</returns>
         public bool UpdateDz(int id, DropZone dropZone, bool resetCache = true)
         {
             dropZone.Id = id;
@@ -124,4 +158,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Private Fields
     }
-}
\ No newline at end of file
+}
diff --git a/Back/skydiveLogs-api.DomainBusiness/GearService.cs b/Back/skydiveLogs-api.DomainBusiness/GearService.cs
index 1e51c64..2af5772 100644
--- a/Back/skydiveLogs-api.DomainBusiness/GearService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/GearService.cs
@@ -32,6 +32,10 @@ namespace skydiveLogs_api.DomainBusiness
             var userId = _identityService.ConnectedUser.Id;
             _cacheService.Delete(CacheType.Gear, userId: userId);
         }
+        /// <summary>
+        /// Adds a new gear item to the system.
+        /// </summary>
+        /// <param name="newGear">The Gear entity containing the new gear data.</param>
 
         public void AddRentalGear(User newUser)
         {
@@ -49,11 +53,19 @@ namespace skydiveLogs_api.DomainBusiness
 
             _gearRepository.Add(rentalGear);
         }
+        /// <summary>
+        /// Adds rental gear to the system for a new user.
+        /// </summary>
+        /// <param name="newUser">The new user for whom rental gear should be added.</param>
 
         public void DeleteGearById(int id)
         {
             throw new NotImplementedException();
         }
+        /// <summary>
+        /// Deletes a gear item by its ID.
+        /// </summary>
+        /// <param name="id">The gear ID to delete.</param>
 
         public IEnumerable<Gear> GetAllGears()
         {
@@ -66,12 +78,21 @@ namespace skydiveLogs_api.DomainBusiness
 
             return _cacheService.Get<IEnumerable<Gear>>(CacheType.Gear, userId: userId);
         }
+        /// <summary>
+        /// Retrieves all gear items.
+        /// </summary>
+        /// <returns>A collection of Gear entities containing all gear data.</returns>
 
         public Gear GetGearById(int id)
         {
             var allGears = GetAllGears();
             return allGears.Single(g => g.Id == id);
         }
+        /// <summary>
+        /// Retrieves a gear item by its ID.
+        /// </summary>
+        /// <param name="id">The gear ID to retrieve.</param>
+        /// <returns>A Gear entity containing the gear details.</returns>
 
         public bool UpdateGear(int id, Gear gear)
         {
@@ -79,6 +100,12 @@ namespace skydiveLogs_api.DomainBusiness
 
             return _gearRepository.Update(gear);
         }
+        /// <summary>
+        /// Updates an existing gear item.
+        /// </summary>
+        /// <param name="id">The gear ID to update.</param>
+        /// <param name="gear">Gear entity containing the updated gear data.</param>
+        /// <returns>True if the update was successful, false otherwise.</returns>
 
         #endregion Public Methods
 
@@ -90,4 +117,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Private Fields
     }
-}
\ No newline at end of file
+}
diff --git a/Back/skydiveLogs-api.DomainBusiness/InitDbService.cs b/Back/skydiveLogs-api.DomainBusiness/InitDbService.cs
index 541d8bc..ceca1ea 100644
--- a/Back/skydiveLogs-api.DomainBusiness/InitDbService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/InitDbService.cs
@@ -27,6 +27,9 @@ namespace skydiveLogs_api.DomainBusiness
 
         #region Public Methods
 
+        /// <summary>
+        /// Updates the existing data in the database.
+        /// </summary>
         public void Update()
         {
             UpdateAircrafts();
@@ -38,6 +41,9 @@ namespace skydiveLogs_api.DomainBusiness
             _cacheService.Delete(CacheType.JumpType);
         }
 
+        /// <summary>
+        /// Generates the database structure and initial data.
+        /// </summary>
         public void GenerateDb()
         {
             LoadAircrafts();
@@ -193,4 +199,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Private Fields
     }
-}
\ No newline at end of file
+}
diff --git a/Back/skydiveLogs-api.DomainBusiness/JumpService.cs b/Back/skydiveLogs-api.DomainBusiness/JumpService.cs
index c96e120..b445fa1 100644
--- a/Back/skydiveLogs-api.DomainBusiness/JumpService.cs
+++ b/Back/skydiveLogs-api.DomainBusiness/JumpService.cs
@@ -28,6 +28,14 @@ namespace skydiveLogs_api.DomainBusiness
 
         #region Public Methods
 
+        /// <summary>
+        /// Adds a new jump to the system.
+        /// </summary>
+        /// <param name="aircraftId">The ID of the aircraft to use for this jump.</param>
+        /// <param name="dzId">The ID of the drop zone for this jump.</param>
+        /// <param name="jumpTypeId">The ID of the jump type for this jump.</param>
+        /// <param name="gearId">The ID of the gear for this jump.</param>
+        /// <param name="jump">Jump entity containing the new jump data.</param>
         public void AddNewJump(int aircraftId,
                                int dzId,
                                int jumpTypeId,
@@ -48,31 +56,59 @@ namespace skydiveLogs_api.DomainBusiness
             _jumpRepository.Add(jump);
         }
 
+        /// <summary>
+        /// Deletes a jump by its ID.
+        /// </summary>
+        /// <param name="id">The jump ID to delete.</param>
         public void DeleteJumpById(int id)
         {
             _jumpRepository.DeleteById(id);
         }
 
+        /// <summary>
+        /// Retrieves all jumps for the current user.
+        /// </summary>
+        /// <returns>A collection of Jump entities containing all jumps.</returns>
         public IEnumerable<Jump> GetAllJumps()
         {
             return _jumpRepository.GetAll(_identityService.ConnectedUser);
         }
 
+        /// <summary>
+        /// Retrieves a jump by its ID.
+        /// </summary>
+        /// <param name="id">The jump ID to retrieve.</param>
+        /// <returns>A Jump entity containing the jump details.</returns>
         public Jump GetJumpById(int id)
         {
             return _jumpRepository.GetById(id);
         }
 
+        /// <summary>
+        /// Retrieves the total count of jumps for the current user.
+        /// </summary>
+        /// <returns>The total number of jumps.</returns>
         public int GetJumpCount()
         {
             return _jumpRepository.GetCount(_identityService.ConnectedUser);
         }
 
+        /// <summary>
+        /// Retrieves a range of jumps for the current user with pagination.
+        /// </summary>
+        /// <param name="beginIndex">The starting index for pagination.</param>
+        /// <param name="endIndex">The ending index for pagination.</param>
+        /// <returns>A collection of Jump entities containing the requested range.</returns>
         public IEnumerable<Jump> GetJumpsByIndexes(int beginIndex, int endIndex)
         {
             return _jumpRepository.GetBetweenIndex(_identityService.ConnectedUser, beginIndex, endIndex);
         }
 
+        /// <summary>
+        /// Updates an existing jump.
+        /// </summary>
+        /// <param name="id">The jump ID to update.</param>
+        /// <param name="updatedJump">Jump entity containing the updated jump data.</param>
         public void UpdateJump(int id, Jump updatedJump)
         {
             var myJump = GetJumpById(id);
@@ -96,4 +132,4 @@ namespace skydiveLogs_api.DomainBusiness
 
         #endregion Private Fields
     }
-}
\ No newline at end of file
+}