1. INTRODUCTION

2. DATA
2.1. 3D-HST
2.2. SDSS
2.3. VVDS
2.4. High redshift data

3. THE EW(Hα) - MASS RELATION

4. THE EVOLUTION OF EW(Hα) WITH REDSHIFT

5. THE SSFR(Hα) - MASS RELATION AND ITS EVOLUTION WITH REDSHIFT

6. LINKING THE CHARACTERISTIC SFH OF GALAXIES AND EW(Hα)

7. CONCLUSIONS