We use the Present Simple:
for permanent situations:
• I live in a flat.
• She works for an insurance company.
for repeated actions or habits:
• I use my mobile phone every day.
for general truths:
• The sun rises in the East.
• Matter consists of small particles.
•Water is boiling at 100 degrees.
• Water boils at 100 degrees.
to tell stories, or summarise the plot of a film or book:
• Our hero goes off to search for the treasures, which he eventually finds after many adventures.