As someone else already pointed out, you can use the Batch option by right-clicking the tool in Toolbox. Otherwise, it's hard to know how best to batch it without knowing more about the feature classes and their locations (are they all in the same workspace? are they the only feature classes in that workspace?) and the type of buffers you want to create (e.g. will they all have the same distance)

These things all go into, for instance, whether you're better off just typing in the name of a few feature classes into a list or if you should be using something like arcpy.ListFeatureClasses to generate a list of feature classes to process.

Something as simple as:

import arcpy

arcpy.env.workspace = r'path\to\workspace'
featureClasses = ['fc1', 'fc2', fc3']
for featureClass in featureClasses:
  arcpy.Buffer_analysis(featureClass, "C:/output/" + featureClass + "Buffered" "100 Feet", "FULL", "ROUND", "LIST", "Distance")

would likely take care of it...

As someone else already pointed out, you can use the Batch option by right-clicking the tool in Toolbox. Otherwise, it's hard to know how best to batch it without knowing more about the feature classes and their locations (are they all in the same workspace? are they the only feature classes in that workspace?) and the type of buffers you want to create (e.g. will they all have the same distance)

These things all go into, for instance, whether you're better off just typing in the name of a few feature classes into a list or if you should be using something like arcpy.ListFeatureClasses to generate a list of feature classes to process.

Something as simple as:

import arcpy

arcpy.env.workspace = r'path\to\workspace'
featureClasses = ['fc1', 'fc2', 'fc3']
for featureClass in featureClasses:
  arcpy.Buffer_analysis(featureClass, "C:/output/" + featureClass + "Buffered" "100 Feet", "FULL", "ROUND", "LIST", "Distance")

would likely take care of it...