diff --git a/README.md b/README.md
index 556a266..e3a6a99 100644
--- a/README.md
+++ b/README.md
@@ -74,7 +74,7 @@ fmp_get(resource = "symbol_change", api_version = "v4")
 
 There is an existing Python module that also provide an interface to the FMP API. However, the module lacks flexibility because it provides dedicated functions for specific endpoints, which means that users need to study both the FMP API docs and the package documentation and developers have to create new functions for each new endpoint. 
 
-- [fmp-python](https://pypi.org/project/fmp-python/): last comupdated more than 3 years ago. 
+- [fmp-python](https://pypi.org/project/fmp-python/): last commit more than 3 years ago. 
 
 ## Contributing
 
diff --git a/fmpapi/fmp_get.py b/fmpapi/fmp_get.py
index 47760be..0c78896 100644
--- a/fmpapi/fmp_get.py
+++ b/fmpapi/fmp_get.py
@@ -2,14 +2,15 @@
 import httpx
 import os
 import re
+from typing import Optional, Dict, Any, List
 
 def fmp_get(
-    resource, 
-    symbol=None, 
-    params={},
-    api_version="v3", 
-    snake_case=True
-    ):
+    resource: str, 
+    symbol: Optional[str] = None, 
+    params: Dict[str, Any] = {}, 
+    api_version: str = "v3", 
+    snake_case: bool = True
+) -> pl.DataFrame:
     """
     Retrieve Financial Data from the Financial Modeling Prep (FMP) API
 
@@ -66,11 +67,11 @@ def fmp_get(
     return data_processed
 
 def perform_request(
-    resource, 
-    base_url="https://financialmodelingprep.com/api/", 
-    api_version="v3", 
-    **kwargs
-    ):
+    resource: str, 
+    base_url: str = "https://financialmodelingprep.com/api/", 
+    api_version: str = "v3", 
+    **kwargs: Any
+) -> List[Dict[str, Any]]:
     """
     Perform a GET request to the Financial Modeling Prep (FMP) API.
 
@@ -100,7 +101,7 @@ def perform_request(
     data = response.json()
     return data
 
-def validate_symbol(symbol):
+def validate_symbol(symbol: str) -> None:
     """
     Validate the provided stock ticker symbol.
 
@@ -113,7 +114,7 @@ def validate_symbol(symbol):
     if not isinstance(symbol, str) or len(symbol) == 0:
         raise ValueError("Please provide a valid symbol.")
 
-def validate_period(period):
+def validate_period(period: str) -> None:
     """
     Validate the reporting period parameter.
 
@@ -126,7 +127,7 @@ def validate_period(period):
     if period not in ["annual", "quarter"]:
         raise ValueError("Period must be either 'annual' or 'quarter'.")
     
-def validate_limit(limit):
+def validate_limit(limit: int) -> None:
     """
     Validate the limit parameter for API requests.
 
@@ -139,7 +140,7 @@ def validate_limit(limit):
     if not isinstance(limit, int) or limit < 1:
         raise ValueError("Limit must be an integer larger than 0.")
 
-def convert_column_names(df):
+def convert_column_names(df: pl.DataFrame) -> pl.DataFrame:
     """
     Convert column names in a Polars DataFrame to snake_case.
 
@@ -152,7 +153,7 @@ def convert_column_names(df):
     df = df.rename({col: re.sub(r'([a-z])([A-Z])', r'\1_\2', col).lower() for col in df.columns})
     return df
 
-def convert_column_types(df):
+def convert_column_types(df: pl.DataFrame) -> pl.DataFrame:
     """
     Convert column types in a Polars DataFrame.