Make SEO friendly URL by .htaccess

RewriteEngine On

#Below code replace string value

RewriteRule ^category/([^/\.]+) category.php?tools_category=$1

#Below code replace number value i.e. fetch by id

RewriteRule ^category/([0-9]+) category.php?cat_id=$1

Where 

category.php - is your page name 

Original URL- 1 - http://localhost/kanha/category.php?tools_category=domain

After 1 - http://localhost/kanha/category/domain

Original URL- 2 - http://localhost/kanha/category.php?cat_id=1

After 1 - http://localhost/kanha/category/1