diff --git a/telegram_bot/news/news_fetcher.py b/telegram_bot/news/news_fetcher.py
index 96f50ff..a6dad7e 100644
--- a/telegram_bot/news/news_fetcher.py
+++ b/telegram_bot/news/news_fetcher.py
@@ -15,12 +15,13 @@ import datetime as dt
 from newsapi import NewsApiClient
 from dotenv import load_dotenv
 
-load_dotenv()
+load_dotenv() # loads environment vars
 
 # Init
-api_key = os.getenv('NEWS_API_KEY')
-newsapi = NewsApiClient(api_key=api_key)
+api_key = os.getenv('NEWS_API_KEY') # get API Key from .env file
+newsapi = NewsApiClient(api_key=api_key) # news api from https://newsapi.org/
 try:
+    # get all available news sources (e.g BBC, New York Times, etc.)
     source_json = requests.get(f"https://newsapi.org/v2/top-headlines/sources?apiKey={api_key}&language=en").json()
     sources = source_json["sources"]
     str_sources = ",".join([source["id"] for source in sources])
@@ -38,7 +39,7 @@ def get_all_news_by_keyword(keyword, from_date="2000-01-01"):
     Returns:
         JSON/dict: dict containing articles
     """
-    top_headlines = newsapi.get_everything(q=keyword, sources=str_sources, language='en', from_param=from_date)
+    top_headlines = newsapi.get_everything(q=keyword, sources=str_sources, language='en', from_param=from_date) # keywords can be combined with OR (e.g. keyword = "bitcoin OR ethereum")
     if(top_headlines["status"] == "ok"):
         return top_headlines
     else:
@@ -53,7 +54,7 @@ def get_top_news_by_keyword(keyword):
     Returns:
         JSON/dict: dict containing articles
     """
-    top_headlines = newsapi.get_top_headlines(q=keyword, sources=str_sources, language='en')
+    top_headlines = newsapi.get_top_headlines(q=keyword, sources=str_sources, language='en') # get top headlines, measured by popularity from NewsApi
     if(top_headlines["status"] == "ok"):
         return top_headlines
     else:
@@ -72,11 +73,11 @@ def format_article(article):
     sourcename = article["source"]["name"]
     headline = article["title"]
     url = article["url"]
-    formatted_article = f"_{sourcename}_\n*{headline}*\n\n{url}"
+    formatted_article = f"_{sourcename}_\n*{headline}*\n\n{url}" # formatting in Markdown syntax
 
     return formatted_article
 
-if __name__ == '__main__':
+if __name__ == '__main__': # only execute if script is called directly -> for simple testing
 
     print("this is a module and should not be run directly")
     print("fetching top news by keyword bitcoin...")
@@ -84,4 +85,7 @@ if __name__ == '__main__':
     articles = get_all_news_by_keyword("bitcoin")
     formatted_article = format_article(articles["articles"][0])
     print(formatted_article)
+    articles = get_top_news_by_keyword("bitcoin")
+    formatted_article = format_article(articles["articles"][0])
+    print(formatted_article)
     sys.exit(1)
\ No newline at end of file