Need some help explaining the code

[harryc1127]

Could someone explain whats going on in this little segment of code? what each line does if possible please

        static string[] groups = { "AEIOUHWY", "BFPV", "CGJKQSXZ", "DT", "L", "MN", "R" }; 
 
       static string getCode(string str)
        {
            string tempstr = "";
            int i;
 
            for (i = 0; i < 7; i++)
            {
                if (groups[i].Contains(str))
                {
                    tempstr = i.ToString();
                    break;
                }
            }
            return tempstr;
        }
 
        static string encodeString(string str)
        {
            string tempstr = "";
            int i;
 
            for (i = 0; i < str.Length; i++)
            {
                tempstr = tempstr + getCode(str.Substring(i, 1));
            }
            return tempstr;
        }
 

        static string removeZeroes(string str)
        {
            string tempstr = "";
            int i;
 

            for (i = 0; i < str.Length; i++)
            {
                if (str.Substring(i, 1) != "0")
                {
                    tempstr = tempstr + str.Substring(i, 1);
                }
            }
            return tempstr;
        }
 
        static string RemoveAdjacent(string str)
        {
            string tempstr = "";
            int i;
 
            string stringToCheckAgainst = "#";
 
            for (i = 0; i < str.Length; i++)
            {
                if (str.Substring(i, 1) != stringToCheckAgainst)
                {
                    tempstr = tempstr + str.Substring(i, 1);
                    stringToCheckAgainst = str.Substring(i, 1);
                }
            }
            return tempstr;
        }
    }
}