diff --git a/BoerseDataConvert/BoerseDataConvert/Controller/RecordController.cs b/BoerseDataConvert/BoerseDataConvert/Controller/RecordController.cs
index d243e05..f8e2b53 100644
--- a/BoerseDataConvert/BoerseDataConvert/Controller/RecordController.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Controller/RecordController.cs
@@ -20,6 +20,12 @@ namespace BoerseDataConvert
         {
             get { return count - 1; }
         }
+        /// <summary>
+        /// It create XML writer,xml file, writes the first line in it
+        /// </summary>
+        /// <param name="adr">output directoty</param>
+        /// <param name="fileName">currnt file name</param>
+        /// <param name="tags">Locataion of tags,txt</param>
         public RecordController(string adr, string fileName, string tags)
         {
             count = 1;
@@ -36,6 +42,11 @@ namespace BoerseDataConvert
             writer.WriteAttributeString("name", null, cur_fileName);
             warning = new WarningStat(fileName);
         }
+        /// <summary>
+        /// It writes the last line, closes the flie, and XMLwriter
+        /// and It creates new XML writer,new xml file, writes the first line in it
+        /// </summary>
+        /// <param name="fileName">name of the next file</param>
         public static void NextFile(string fileName)
         {
             writer.WriteEndElement();
@@ -54,13 +65,27 @@ namespace BoerseDataConvert
             writer.WriteStartElement("table");
             writer.WriteAttributeString("name", null, cur_fileName);
         }
-        public void WriteXmlRecord(Record record)
+        /// <summary>
+        /// It write the information in the record into the XML file
+        /// </summary>
+        /// <param name="record">Record that stores information about one record from the files</param>
+        /// <param name="fastCheck">if true it makes a fastChech</param>
+        public void WriteXmlRecord(Record record,bool fastCheck)
         {
             writer.WriteStartElement("record");
             writer.WriteAttributeString("id", null, count.ToString());
             foreach (var tagValue in record)
             {
-                string tag = CheckTagValue(tagValue.Key, tagValue.Value);
+                string tag = "";
+                if (fastCheck)
+                {
+                    tag = FastChechTag(tagValue.Key);
+                }
+                else 
+                {  
+                    tag = FullCheckTagValue(tagValue.Key, tagValue.Value);
+                }
+                
                 if (tag != null)
                 {
                     writer.WriteStartElement(tag);
@@ -78,7 +103,30 @@ namespace BoerseDataConvert
             writer.Close();
             warning.PrintWarnigs();
         }
-        private string CheckTagValue(int tag, string value)
+        /// <summary>
+        /// It checks only if the tag is valid
+        /// </summary>
+        /// <param name="tag">tag in the numeric form</param>
+        /// <returns>return name of the tag</returns>
+        private string FastChechTag(int tag)
+        {
+            if (tagsTable.CheckInvalidTag(tag))
+            {
+                warning.Add(tag);
+                return null;
+            }
+            else
+            {
+                return tagsTable.GetTagName(tag);
+            }
+        }
+        /// <summary>
+        /// It make a full check on the value
+        /// </summary>
+        /// <param name="tag">tag in the numeric form</param>
+        /// <param name="value"></param>
+        /// <returns>return name of the tag</returns>
+        private string FullCheckTagValue(int tag, string value)
         {
             if (tagsTable.CheckInvalidTag(tag))
             {
diff --git a/BoerseDataConvert/BoerseDataConvert/Model/Record.cs b/BoerseDataConvert/BoerseDataConvert/Model/Record.cs
index 99732eb..e8e1b69 100644
--- a/BoerseDataConvert/BoerseDataConvert/Model/Record.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Model/Record.cs
@@ -7,19 +7,30 @@ using System.Threading.Tasks;
 
 namespace BoerseDataConvert
 {
-
+    /// <summary>
+    /// Class Recorrd stores information about the tags and the values of every record 
+    /// </summary>
     public class Record : IEnumerable
     {
+        //The tags and the values are stored in list from KeyValuePair where the tags are the keys
         private List<KeyValuePair<int, string>> TagsValues;
 
         public Record()
         {
             TagsValues = new List<KeyValuePair<int, string>>();
         }
+        /// <summary>
+        /// This method adds a new TagValuePair in the TagsValues
+        /// </summary>
+        /// <param name="tag"></param>
+        /// <param name="value"></param>
         public void Add(int tag, string value)
         {
             TagsValues.Add(new KeyValuePair<int, string>(tag, value));
         }
+        /// <summary>
+        /// The iterator for class Record
+        /// </summary>
         public IEnumerator<KeyValuePair<int, string>> GetEnumerator()
         {
             foreach (var item in TagsValues)
diff --git a/BoerseDataConvert/BoerseDataConvert/Model/Tag.cs b/BoerseDataConvert/BoerseDataConvert/Model/Tag.cs
index 7741485..18528ed 100644
--- a/BoerseDataConvert/BoerseDataConvert/Model/Tag.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Model/Tag.cs
@@ -6,6 +6,9 @@ using System.Threading.Tasks;
 
 namespace BoerseDataConvert
 {
+    /// <summary>
+    /// This class stores the name,the type and the value ranges for one tag 
+    /// </summary>
     public class Tag
     {
         private string name;
@@ -31,22 +34,37 @@ namespace BoerseDataConvert
             }
             else haveValueRanges = false;
         }
+        /// <summary>
+        /// Returns the name of the tag 
+        /// </summary>
         public string Name
         {
             get { return name; }
         }
+        /// <summary>
+        /// Returns true if the type of the tag is string 
+        /// </summary>
         public bool IsString
         {
             get { return isString; }
         }
+        /// <summary>
+        /// Returns true if  the tag has a value ranges
+        /// </summary>
         public bool HaveValueRanges
         {
             get { return haveValueRanges; }
         }
+        /// <summary>
+        /// Returns max length of the string value
+        /// </summary>
         public int StringLength
         {
             get { return stringLength; }
         }
+        /// <summary>
+        /// Returns true if the value is in the value ranges
+        /// </summary>
         public bool ValidValue(string value)
         {
             foreach (string validValue in valueRanges)
diff --git a/BoerseDataConvert/BoerseDataConvert/Model/WarningStat.cs b/BoerseDataConvert/BoerseDataConvert/Model/WarningStat.cs
index 3d228a2..397f03f 100644
--- a/BoerseDataConvert/BoerseDataConvert/Model/WarningStat.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Model/WarningStat.cs
@@ -6,6 +6,9 @@ using System.Threading.Tasks;
 
 namespace BoerseDataConvert
 {
+    /// <summary>
+    /// This class strores information about a invalid tags in a file
+    /// </summary>
     public  class WarningStat
     {
         private Dictionary<int, int> tableWarnings;
@@ -15,7 +18,11 @@ namespace BoerseDataConvert
             curFile = fileName;
             tableWarnings = new Dictionary<int, int>();
         }
-        public  void Add(int tag)
+        /// <summary>
+        /// It increases count of encounters if the invalid tag or it sets it to 1 if the tag is new
+        /// </summary>
+        /// <param name="tag">Invalid tag in numerical form</param>
+        public void Add(int tag)
         {
             if (tableWarnings.ContainsKey(tag))
             {
@@ -26,6 +33,9 @@ namespace BoerseDataConvert
                 tableWarnings.Add(tag, 1);
             }
         }
+        /// <summary>
+        /// It prints the count of encounters of every invalid tag in the file
+        /// </summary>
         public  void PrintWarnigs()
         {
             if (tableWarnings.Count == 0)
diff --git a/BoerseDataConvert/BoerseDataConvert/Views/Program.cs b/BoerseDataConvert/BoerseDataConvert/Views/Program.cs
index dd460a8..6747fd3 100644
--- a/BoerseDataConvert/BoerseDataConvert/Views/Program.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Views/Program.cs
@@ -15,6 +15,7 @@ namespace BoerseDataConvert
         static string outputDirectory;
         static string tagsFile;
         static bool helpMessage;
+        static bool fastCheck;
         static void Main(string[] args)
         {
             /* 
@@ -48,6 +49,7 @@ namespace BoerseDataConvert
                 "The working directory is cleared recursively if it isn't empty!",
                 { "o|output=", "specify output directory", x => outputDirectory = x },
                 { "t|tags=", "specify tag file", x =>  tagsFile = x },
+                { "f|fast|fastcheck=", "specify tag file", x =>  fastCheck = true },
                 { "<>", v => throw new ArgumentException("ERROR: Invalid arguments") }, // default
                 "",
                 "Created by D. Delchev and D. Byalkov, 2021"
@@ -87,7 +89,7 @@ namespace BoerseDataConvert
                 try
                 {
                     Record record = reader.ReadLineRecord();
-                    a.WriteXmlRecord(record);
+                    a.WriteXmlRecord(record,fastCheck);
                 }
                 catch (IndexOutOfRangeException)
                 {
diff --git a/BoerseDataConvert/BoerseDataConvert/Views/Reader.cs b/BoerseDataConvert/BoerseDataConvert/Views/Reader.cs
index b94d866..53d795f 100644
--- a/BoerseDataConvert/BoerseDataConvert/Views/Reader.cs
+++ b/BoerseDataConvert/BoerseDataConvert/Views/Reader.cs
@@ -16,6 +16,11 @@ namespace BoerseDataConvert
         private static StreamReader reader;
         private static int fileInd;
         private string adr;
+        /// <summary>
+        /// it create a reader for first file, start the StopWatch and Checks the first line from the current file
+        /// </summary>
+        /// <param name="adr">input directoty</param>
+        /// <param name="_filesNames">array with the names of the every TXT file</param>
         public Reader(string adr, string[] _filesNames)
         {
             fileInd = 0;
@@ -26,6 +31,11 @@ namespace BoerseDataConvert
             stopwatch.Start();
             CheckFirstLine(date);
         }
+        /// <summary>
+        /// It reads a line from the current file and return a Record with this information
+        /// and it goes to next file if it the current file ends
+        /// </summary>
+        /// <returns>Record with information from 1 line from current file</returns>
         public Record ReadLineRecord()
         {
             string s = reader.ReadLine();
@@ -42,6 +52,12 @@ namespace BoerseDataConvert
             }
             return record;
         }
+        /// <summary>
+        /// it checks the last line from the current file, closes the reader, create a new reader for he file
+        /// also it check first line from the next file and synchronizes a current file in RecordController with its current file
+        /// </summary>
+        /// <param name="s"></param>
+        /// <returns></returns>
         private string NextFile(string s)
         {
             CheckFinalLine(s);
@@ -55,6 +71,10 @@ namespace BoerseDataConvert
             s = reader.ReadLine();
             return s;
         }
+        /// <summary>
+        /// it checks if string date is in the correct format
+        /// </summary>
+        /// <param name="date">first line from a file</param>
         private void CheckFirstLine(string date)
         {
             try
@@ -68,6 +88,10 @@ namespace BoerseDataConvert
                 Console.WriteLine($"WARN: Invalid date in file {filesNames[fileInd]}");
             }
         }
+        /// <summary>
+        /// Checks if string s is in the correct format
+        /// </summary>
+        /// <param name="s">last line from a file</param>
         private void CheckFinalLine(string s)
         {
             if ("Datensaetze: " != s.Substring(0, 13))
@@ -93,6 +117,9 @@ namespace BoerseDataConvert
 
             }
         }
+        /// <summary>
+        /// Closes the reader, stops the stopwatch,print the its time, resets it and start it again
+        /// </summary>
         internal static void EndFile()
         {
             reader.Close();